Item 1

https://backpack.tf/item/11666610021

Sale #1

Untraceable-

Seller: https://backpack.tf/profiles/76561198277936421#!/compare/1679961600/1687824000

Buyer: https://backpack.tf/profiles/76561198311498888#!/compare/1688083200/1688256000

Item 2

https://backpack.tf/item/11000076420

Sale #2

Sold for 24 keys (ID "13321178304" of the unusual matches)-

Seller: https://backpack.tf/profiles/76561199240976002#!/compare/1690761600/1690848000

Buyer: https://backpack.tf/profiles/76561198168506402#!/compare/1639526400/1690934400

Marketplace.tf Sales

https://marketplace.tf/items/tf2/31242;5;u205

MP.TF Sale #1

Sold for $54.95 on May 7

Keys @ $2.03

54.95/2.03 = 27.07ish keys

MP.TF Sale #2

Sold for $54.95 on June 22, 2023

Keys @ $1.98

54.95/1.98 = 27.75ish keys

MP.TF Sale #3

Sold for $41.95 on July 14, 2023

Keys @ $1.95

41.95/1.95 = 21.51ish keys

MP.TF Sale #4

Sold for $41.95 on July 18, 2023

Keys @ $1.97

41.95/1.97 = 21.29ish keys

Sales @ 21, 22, 24, 27, 28

Taking 21-24 here