Item 1

https://backpack.tf/item/16135688311

Sale 1

https://backpack.tf/profiles/76561198204384663#!/compare/1758412800/1758758400

https://backpack.tf/profiles/76561198161437557#!/compare/1758672000/1758758400

No clue

Item 2

https://backpack.tf/item/16057714944

Sale 2

https://backpack.tf/profiles/76561198239176176#!/compare/1755993600/1757462400

https://backpack.tf/profiles/76561198877320307#!/compare/1755907200/1755993600

No clue

Sale 3

https://backpack.tf/profiles/76561198877320307#!/compare/1755993600/1756166400

https://backpack.tf/profiles/76561198008883658#!/compare/1756857600/1757721600

No clue

Item 3

https://backpack.tf/item/16013809833

Sale 4

https://backpack.tf/profiles/76561199059632349#!/compare/1755129600/1755216000

https://backpack.tf/profiles/76561198880462190#!/compare/1754611200/1755561600

No clue

Item 4

https://backpack.tf/item/15985114944

Sale 5

https://backpack.tf/profiles/76561198096625145#!/compare/1754697600/1755043200

https://backpack.tf/profiles/76561198099780438#!/compare/1754352000/1755993600

25 keys (16042789137)

Item 5

https://backpack.tf/item/15976445140

Sale 6

https://backpack.tf/profiles/76561198098384995#!/compare/1753747200/1754179200

https://backpack.tf/profiles/76561198161586574#!/compare/1753315200/1754697600

SCM?

Item 6

https://backpack.tf/item/15969263549

Just mannco.store

Item 7

https://backpack.tf/item/15995771766

Sale 7

https://backpack.tf/profiles/76561198320688865#!/compare/1755561600/1755734400

https://backpack.tf/profiles/76561198859721638#!/compare/1755561600/1755648000

Bulk for a Knight's Prideful Spirit Herald's Helm + Fountain of Delight Taunt: Kazotsky Kick

Item 8

https://backpack.tf/item/16051004102

Sale 8

https://backpack.tf/profiles/76561198119434974#!/compare/1757548800/1757635200

https://backpack.tf/profiles/76561198349848918#!/compare/1757462400/1757548800

Dumped for an unknown amount

Sale 9

https://backpack.tf/profiles/76561198349848918#!/compare/1758412800/1758499200

https://backpack.tf/profiles/76561198260699005#!/compare/1758412800/1758499200

24 keys (16196432917) => Keys come from the dumped Archer's Sterling

Sale 10

https://backpack.tf/profiles/76561198260699005#!/compare/1758499200/1759536000

https://backpack.tf/profiles/76561198349848918#!/compare/1758672000/1758758400

Re-dumped for an unknown amount

Item 9

https://backpack.tf/item/15968678971

Sale 11

https://backpack.tf/profiles/76561199436640904#!/compare/1757721600/1757894400

No clue

Mp.tf

https://marketplace.tf/items/tf2/31536;5;u379

$79.99 / $1.81 = ~44 keys (Sep 8)

Total Sales

24, 25, 44

https://imgur.com/a/fFMggN8

44 feels like an outlier here

Going with 24 - 25 keys c:

Unsolds:

https://backpack.tf/item/16051004102 - 40

https://backpack.tf/item/15968678971 - $82.39

https://backpack.tf/item/16072086569 - $82.39

https://backpack.tf/item/16135688311 - 50

https://backpack.tf/item/15995771766 - 100

SCM - $127.84, $130.00, $145.59, $150.00