Many thanks to Icycrevasse for the help!

Item 1

https://backpack.tf/item/12111126756

Sale #1

Sold with a pair of earbuds for a Tesla Coil Tipped Lid? (seems too high, probably something missing?)-

Seller: https://backpack.tf/profiles/76561198904516992#!/compare/1680739200/1680825600

Buyer: https://backpack.tf/profiles/76561198439498211#!/compare/1680739200/1680825600

Sale #2

Sold with a Cloud 9 Patriot Peak + a pair of earbuds for a Sunbeams Dr's Dapper Topper (using this sale to price the Peak, would be bulk for this anyways)-

Seller: https://backpack.tf/profiles/76561198439498211#!/compare/1680739200/1680825600

Buyer: https://backpack.tf/profiles/76561198057954897#!/compare/1680739200/1680825600

Sale #3

Untraceable-

Seller: https://backpack.tf/profiles/76561198057954897#!/compare/1680998400/1681084800

Buyer: https://backpack.tf/profiles/76561198259520701#!/compare/1680480000/1681084800

Sale #4

Sold with a key for a Miami Nights Texas Ten Gallon (49.5 keys) = 48.5 keys-

Seller: https://backpack.tf/profiles/76561198259520701#!/compare/1680480000/1681084800

Buyer: https://backpack.tf/profiles/76561198062047395#!/compare/1671062400/1681084800

Sale #5

Untraceable-

Seller: https://backpack.tf/profiles/76561198062047395#!/compare/1682208000/1684108800

Buyer: https://backpack.tf/profiles/76561198180475779#!/compare/1671494400/1683158400

Sale #6

20 keys appear on the buyer's side but very likely that we are missing things, untraceable-

Seller: https://backpack.tf/profiles/76561198180475779#!/compare/1683331200/1684108800

Buyer: https://backpack.tf/profiles/76561198981792531#!/compare/1683504000/1683849600

Sale #7

Sold for 47 keys + 16 refined-

Seller: https://backpack.tf/profiles/76561198981792531#!/compare/1687478400/1687737600

Buyer: https://backpack.tf/profiles/76561198316831771#!/compare/1687651200/1687737600

Marketplace.tf Sale #1

Sold for $139.99 on June 17, 2023

Keys @ $2.02

139.99/2.02 = 69.30ish keys

Sales @ 47, 49, 69

Taking 49 flat here as a conservative drop