Credit to !Extazi, Vege and Blaze.xTH3RM4Lx for the help - https://next.backpack.tf/suggestions/63064fc8c0fcbcd6110253cb

Sale 1)

https://backpack.tf/item/2978486469

https://backpack.tf/profiles/76561198057452720#!/compare/1661040000/1661126400

https://backpack.tf/profiles/76561198072999396#!/compare/1661040000/1661126400

Bulk

Sale 2)

https://backpack.tf/profiles/76561198118701901#!/compare/1660003200/1660089600

https://backpack.tf/profiles/76561198057452720#!/compare/1659916800/1660003200

Bulk

Sale 3)

https://marketplace.tf/items/tf2/30140;5;u57

1380/1.9 = 726 Keys = ~730 Keys

Sale 4)

https://backpack.tf/profiles/76561198867208675#!/compare/1663804800/1664323200

https://backpack.tf/profiles/76561198867208675#!/compare/1663804800/1664323200

https://gladiator.tf/time-machine?item=Terror-Watt+Virtual+Viewfinder&at=2022-09-26T08%3A05%3A00.000Z listing at 689 keys

It appears to be 646 keys, so we can round to ~650 keys

Sale 5) Gift or Cash trade

https://backpack.tf/item/12022634678

Seller: https://backpack.tf/profiles/76561198059098316#!/compare/1660953600/1661040000

Buyer:

https://backpack.tf/profiles/76561198059778321#!/compare/1660953600/1661558400

Sale 6) Brain Drain Tundra Top and Terror Watt Virtual ViewFinder for Pumpkin Moon Professional's Pom Pom - Better used there

https://backpack.tf/item/12187243317

Seller:

https://backpack.tf/profiles/76561198045343680#!/compare/1664668800/1664928000

Buyer:

https://backpack.tf/profiles/76561198097499917#!/compare/1664668800/1665792000

Sale 7) No Snapshot

https://backpack.tf/item/12153453898

Seller:

https://backpack.tf/profiles/76561198072999396#!/compare/1662508800/1662595200

Buyer:

https://backpack.tf/profiles/76561198041460359#!/compare/1661126400/1663200000

8) 700 keys in mix

https://backpack.tf/profiles/76561198114151975#!/compare/1668038400/1668297600

https://backpack.tf/profiles/76561198049369308#!/compare/1668038400/1668297600 - sold for Nebula Universal Translator + Frozen Icefall Bat Hat + Green Giggler King Cardbeard + 70 keys + the strange parts in the second compare

Mini for Nebula Universal Translator - https://backpack.tf/suggestion/638e1b90e826cadd0b0097fc - 475 - 495 keys or an average of 485 keys

Mini for Frozen Icefall Bat Hat - 112 keys

https://backpack.tf/item/8362060733

https://backpack.tf/profiles/76561198453530349#!/compare/1660867200/1660953600

https://backpack.tf/profiles/76561198044719739#!/compare/1660521600/1660953600

https://gladiator.tf/time-machine?item=Frozen+Icefall+Bat+Hat&at=2022-08-19T14%3A09%3A00.000Z

Mini for Green Giggler King Cardbeard --- 16 keys

Sold for a Terror-Watt Towering Pillar of Hats

https://backpack.tf/profiles/76561198069155154#!/compare/1647561600/1668556800

https://backpack.tf/profiles/76561198188093413#!/compare/1668384000/1668470400

https://gladiator.tf/time-machine?item=Green+Giggler+King+Cardbeard&at=2022-11-15T15%3A09%3A00.000Z B/O 26 Keys and buy orders at 16 keys going 16 keys flat

Allied healing (1.85 keys) https://backpack.tf/stats/Unique/Strange%20Part%3A%20Allied%20Healing%20Done/Tradable/Craftable

Critical kills ~ 1 key - https://backpack.tf/stats/Unique/Strange%20Part%3A%20Critical%20Kills/Tradable/Craftable

Dominations ~ 5 keys - https://backpack.tf/stats/Unique/Strange%20Part%3A%20Domination%20Kills/Tradable/Craftable

Players Hit 1.4 keys - https://backpack.tf/stats/Unique/Strange%20Part%3A%20Player%20Hits/Tradable/Craftable

2 gib kills ~ 1.4 keys each *2 = 2.8 keys = https://backpack.tf/stats/Unique/Strange%20Part%3A%20Gib%20Kills/Tradable/Craftable

Damage Dealt - ~ 6.1 keys - https://backpack.tf/stats/Unique/Strange%20Part%3A%20Damage%20Dealt/Tradable/Craftable

This is about ~ 20 keys in strange parts

485 + 112 + 16 + 70 + 20 = ~ 703 keys = ~ 700 keys

This sale will lie in the between the current range.

9) 600 keys in mix

https://backpack.tf/profiles/76561198054472162#!/compare/1667865600/1667952000

https://backpack.tf/profiles/76561198114151975#!/compare/1667952000/1668038400 - sold for Neutron Star Vive La France + Nebula Universal Translator + 50 keys

Mini for Nebula Universal Translator - https://backpack.tf/suggestion/638e1b90e826cadd0b0097fc - 475 - 495 keys or an average of 485 keys

Mini for Neutron Star Vive La France

Sold with scorching flames merc's mohawk and 5 keys for It's a Secret to Everybody Tartan Spartan

https://backpack.tf/item/5203029511

https://backpack.tf/profiles/76561198045518417#!/compare/1666915200/1668729600

https://backpack.tf/profiles/76561198114151975#!/compare/1666915200/1667088000

https://gladiator.tf/time-machine?item=Neutron+Star+Vive+La+France&at=2022-10-28T14%3A09%3A00.000Z B/O at 130 keys and buy orders at 68 keys

Using Buy orders at 68 keys

485 + 50 + 68 = 603 keys = ~ 600 keys

Sales:

730

646

700

600

Going 600 - 730 keys or an average of 665 keys.