Heya there just checked on your suggestion and there's a lot of sales that have happened or that you missed when suggesting this so I'll be including them here!

Item 1

https://backpack.tf/item/13652418515

Ignoring the trade-back between STN bots and Comet

Sale #1

Untraceable?-

Seller: https://backpack.tf/profiles/76561198122235273#!/compare/1702598400/1709164800

Buyer: https://backpack.tf/profiles/76561199103991885#!/compare/1702512000/1702598400

Sale #2

Untraceable? Was a dump anyways-

Seller: https://backpack.tf/profiles/76561199103991885#!/compare/1702771200/1702857600

Buyer: https://backpack.tf/profiles/76561199026390261#!/compare/1702771200/1702857600

Sale #3

Sold for 50 keys + 19 refined (keys in the buyer's side match)-

Seller: https://backpack.tf/profiles/76561199026390261#!/compare/1704758400/1704844800

Buyer: https://backpack.tf/profiles/76561198114556179#!/compare/1704758400/1704844800

Item 2

https://backpack.tf/item/13658803872

Sale #4

Untraceable? None of the keys in the buyer's side match-

Seller: https://backpack.tf/profiles/76561198243398038#!/compare/1697760000/1697932800

Buyer: https://backpack.tf/profiles/76561198090750997#!/compare/1697673600/1697760000

Sale #5

Untraceable?-

Seller: https://backpack.tf/profiles/76561198205126119#!/compare/1703548800/1706572800

Buyer: https://backpack.tf/profiles/76561198168976496#!/compare/1705708800/1706486400

Item 3

https://backpack.tf/item/13658923357

Sale #6

Sold for a Revenant's Rack Ludicrously Lunatic Lunon Fedora (40 keys) (ID "13810976806" of the unusual matches)-

Seller: https://backpack.tf/profiles/76561199075307750#!/compare/1700265600/1707004800

Buyer: https://backpack.tf/profiles/76561199523946153#!/compare/1700179200/1700265600

Sale #7

Sold for 21 keys + 46 refined (keys in the buyer's side match)-

Seller: https://backpack.tf/profiles/76561199523946153#!/compare/1700265600/1700352000

Buyer: https://backpack.tf/profiles/76561198107209284#!/compare/1700265600/1700352000

Sale #8

Sold for 25 keys (keys in the buyer's side match)-

Seller: https://backpack.tf/profiles/76561198107209284#!/compare/1700870400/1701043200

Buyer: https://backpack.tf/profiles/76561198067781788#!/compare/1700956800/1701043200

Sale #9

Bulk sale-

Seller: https://backpack.tf/profiles/76561198067781788#!/compare/1702166400/1702252800

Buyer: https://backpack.tf/profiles/76561198261483133#!/compare/1702166400/1702252800

Sale #10

Sold for 31 keys + a Flapjack (36 refined or 0.46ish keys, taking specifc buyers for the paint) (ID "14107172511" of the unusual matches) = 31.46ish keys-

Seller: https://backpack.tf/profiles/76561198261483133#!/compare/1706486400/1706572800

Buyer: https://backpack.tf/profiles/76561198186607323#!/compare/1706486400/1706572800

Sale #11

Sold for 31 keys (key in the buyer's side match)-

Seller: https://backpack.tf/profiles/76561198186607323#!/compare/1707177600/1707264000

Buyer: https://backpack.tf/profiles/76561199082903145#!/compare/1707177600/1707264000

Sale #12

Untraceable?-

Seller: https://backpack.tf/profiles/76561199082903145#!/compare/1711065600/1713830400

Buyer: https://backpack.tf/profiles/76561198070248296#!/compare/1712966400/1713052800

Item 4

https://backpack.tf/item/13660571989

Sale #13

Sold for 45 keys (ID '13744259937" of the unusual matches)-

Seller: https://backpack.tf/profiles/76561198067200487#!/compare/1698710400/1698883200

Buyer: https://backpack.tf/profiles/76561198078240812#!/compare/1698796800/1699228800

Item 5

https://backpack.tf/item/13662586993

Sale #14

Bulk sale-

Seller: https://backpack.tf/profiles/76561198161385366#!/compare/1699747200/1699920000

Buyer: https://backpack.tf/profiles/76561198261483133#!/compare/1699660800/1699747200

Sale #15

Sold for 39 keys (ID '13823960929" of the unusual matches)-

Seller: https://backpack.tf/profiles/76561198261483133#!/compare/1700524800/1700611200

Buyer: https://backpack.tf/profiles/76561198393570312#!/compare/1700438400/1700611200

Sale #16

Gambled?-

Seller: https://backpack.tf/profiles/76561198393570312#!/compare/1702944000/1703116800

Buyer: https://backpack.tf/profiles/76561199161916038#!/compare/1702857600/1702944000

Sale #17

Gambled-

Seller: https://backpack.tf/profiles/76561199161916038#!/compare/1702944000/1703030400

Buyer: https://backpack.tf/profiles/76561198054722733#!/compare/1703030400/1703116800

Sale #18

Untraceable?-

Seller: https://backpack.tf/profiles/76561198054722733#!/compare/1703030400/1703116800

Buyer: https://backpack.tf/profiles/76561199389372563#!/compare/1702944000/1703030400

Sale #19

Transferred from bot to owner or untraceable?-

Seller: https://backpack.tf/profiles/76561199389372563#!/compare/1703030400/1703116800

Buyer: https://backpack.tf/profiles/76561198117597416#!/compare/1703030400/1703116800

Item 6

https://backpack.tf/item/13672845857

Sale #20

Only two random hats trace when using ID "13744246888" of the unusual, incomplete?-

Seller: https://backpack.tf/profiles/76561199155091266#!/compare/1698796800/1711584000

Buyer: https://backpack.tf/profiles/76561198068068814#!/compare/1698796800/1698883200

Sale #21

Sold for a Green Confetti Climbing Commander + an Arachne's Web Dell Dynamic + a Massed Flies Towering Titanium Pillar of Hats (10 keys) + a Non-Craftable Burstchester Unusualifier + 44 refined (ID "13744607634" of the unusual matches)-

Seller: https://backpack.tf/profiles/76561198068068814#!/compare/1698796800/1698883200

Buyer: https://backpack.tf/profiles/76561199157328830#!/compare/1698796800/1698883200

Sale #22

Untraceable?-

Seller: https://backpack.tf/profiles/76561199157328830#!/compare/1698796800/1698883200

Buyer: https://backpack.tf/profiles/76561199477114346#!/compare/1698624000/1698969600

Sale #23

Untraceable?-

Seller: https://backpack.tf/profiles/76561199477114346#!/compare/1698969600/1699056000

Buyer: https://backpack.tf/profiles/76561198108287095#!/compare/1698969600/1698969600

Sale #24

Untraceable?-

Seller: https://backpack.tf/profiles/76561198108287095#!/compare/1698969600/1713830400

Buyer: https://backpack.tf/profiles/76561198120672630#!/compare/1698883200/1698969600

Sale #25

Sold for a Stellar Ascent Thunder Dome (26.5 keys) + a Deep-sea Devourer Rancho Relaxo + a Toxic Grip Square Dance (unusuals match histories and can be seen in both sides of the compares)-

Seller: https://backpack.tf/profiles/76561198120672630#!/compare/1698969600/1699056000

Buyer: https://backpack.tf/profiles/76561198217101891#!/compare/1698969600/1699056000

Sale #26

Bulk dump-

Seller: https://backpack.tf/profiles/76561198217101891#!/compare/1700352000/1700697600

Buyer: https://backpack.tf/profiles/76561199084784906#!/compare/1700611200/1700697600

Sale #27

Untraceable?-

Seller: https://backpack.tf/profiles/76561199084784906#!/compare/1700870400/1700956800

Buyer: https://backpack.tf/profiles/76561198049812975#!/compare/1700870400/1700956800

Sale #28

Bulk sale-

Seller: https://backpack.tf/profiles/76561198049812975#!/compare/1702080000/1702166400

Buyer: https://backpack.tf/profiles/76561198261483133#!/compare/1702080000/1702166400

Sale #29

Sold for 40 keys (ID '13934868793" of the unusual matches)-

Seller: https://backpack.tf/profiles/76561198261483133#!/compare/1702857600/1702944000

Buyer: https://backpack.tf/profiles/76561199538132413#!/compare/1702857600/1702944000

u[}Item 7[/u]

https://backpack.tf/item/13673308279

Sale #30

Only 17 refined trace when using ID "14098062887" of the unusual, incomplete but was a dump anyways-

Seller: https://backpack.tf/profiles/76561198023897791#!/compare/1706313600/1708905600

Buyer: https://backpack.tf/profiles/76561198850274253#!/compare/1706227200/1706313600

Sale #31

Sold for 34 keys (key in the buyer's side match)-

Seller: https://backpack.tf/profiles/76561198850274253#!/compare/1706572800/1706659200

Buyer: https://backpack.tf/profiles/76561198091228424#!/compare/1706227200/1706659200

MP.TF Sale #1

Sold for $105 on November 26, 2023

Average Key Price @ $1.71ish

105/1.71 = 61.40ish keys

Unknown History?

https://marketplace.tf/items/tf2/31391;5;u306

Sales @ 22, 25, 31, 31, 34, 39, 40, 40, 45, 50, 61

Not fully min'ing Sale #25 given it was dumped afterwards, Excluding one of the 40s given it was sold for way less afterwards, excluding 22 and 25 given buyers for higher on STN, and excluding 61 given sellers for lower. Should be fine to include 50 here even with seller at 45 given the seller is young and would fall into the range regardless. You could take a range of 31-50 here but I would recommend you to fully mini Sale #21 to prove what it is valued at but I'm pretty sure it would fall into the range regardless!