Thanks to Shuffle for the info!

https://backpack.tf/item/1018167565

Sale 1) Sold for 150 Keys + Sparkling Lights Telefragger Toque + Fragmented Gluons Missing Piece + Festive Spirit Box Trot + Trackman's Touchdown Unusualifier

https://backpack.tf/profiles/76561198114402400#!/compare/1587686400/1587772800

https://imgur.com/a/1o6wUK9 - Capped by the Buyout of 200 Keys

https://backpack.tf/item/345638947

Sale 2) Sold for a Scorching Flames Razor Cut + 12 Keys

https://backpack.tf/profiles/76561198067086489#!/compare/1585526400/1585785600

Not a good sale to use for this or the Razor.

Sale 3) Sold for a Green Energy Mining Light (139 Keys)

https://backpack.tf/profiles/76561198154211785#!/compare/1585872000/1586044800

Low outlier.

Sale 4) Sold for 169 Keys + ~23 Keys of Australiums

https://backpack.tf/profiles/76561198114402400#!/compare/1585958400/1586044800

Excluding as this was part of a tradeback.

Sale 5) Sold + 56 Keys + Green Energy Crocleather Slouch + ~25 Keys of Items/Taunts for a Burning Flames Master's Yellow Belt

https://backpack.tf/profiles/76561198114402400#!/compare/1586736000/1586822400

Better for the Belt + a tradeback, excluding.

Sale 6) Sold for 200 Keys

https://backpack.tf/profiles/76561198114402400#!/compare/1587772800/1587859200

https://backpack.tf/item/282040201

Sale 7) Sold for a Sparkling Lights Patriot Peak + Haunted Ghosts Master's Yellow Belt + Strange Spec KS AWP (~9.5 Keys) + Headtaker (~5.5 Keys)

https://backpack.tf/profiles/76561198114402400#!/compare/1581724800/1581811200

https://imgur.com/a/8ZuRaT1 - Capped by the Buyout of 200 Keys

Peak Mini

https://backpack.tf/profiles/76561198064658655#!/compare/1580256000/1580342400 - Sold for a HG Mining (65 Keys) + SF Festivizer + Pool Party ~3 Keys)

https://backpack.tf/profiles/76561198121628900#!/compare/1581379200/1581638400 - Sold for a Duped Poisoned Shadows Officer's Ushanka

Ushanka Micro

https://backpack.tf/profiles/76561198120672630#!/compare/1582416000/1582502400 - Sold for a Harvest Glengarry + ~50 Keys of other things

https://backpack.tf/profiles/76561198120672630#!/compare/1582329600/1582416000 - Sold + ~17 Keys of Unusuals for a Smoking Veil + Duped RA Bucket

https://backpack.tf/profiles/76561198083134207#!/compare/1580860800/1580947200 - The RA Bucket sold for ~70 Keys

https://backpack.tf/profiles/76561198055622215#!/compare/1581897600/1581984000 - This Bucket sale is better for the Beenie

https://imgur.com/a/2Z0mcUQ - The Veil listing at 72 sold for 75 Keys

https://backpack.tf/profiles/76561198986498652#!/compare/1586037600/1586124000 - The 75 Key Veil sale

Sale 8) Bulk sale for a Golden Frying Pan

https://backpack.tf/profiles/76561198099260958#!/compare/1584057600/1584144000

Sale 9) Sold for $300 when Keys were $1.79 each

https://backpack.tf/profiles/76561198271951717#!/compare/1587081600/1587513600

https://marketplace.tf/items/tf2/110;5;u10

300 / 1.79 = 167.59, which rounds to 168 Keys

Taking 168 - 200 keys