Credit to Mindacos

Sold for $20, 25, $26 and $24 on Marketplace($20 Sale is ~10 Keys using 1.95 value, everything else is an outlier.)

https://marketplace.tf/items/30662;5;u97

Sold for 9 Keys

https://backpack.tf/profiles/76561198059065962#!/compare/1505520000/1505865600

Sold for 10 Keys

https://backpack.tf/profiles/76561198048008254#!/compare/1506643200/1506729600

Sold for 9 Keys

https://backpack.tf/profiles/76561198114863794#!/compare/1507852800/1507939200

https://backpack.tf/item/6183894049

Sold for ~10 Keys in Items

https://backpack.tf/profiles/76561198131633162#!/compare/1511740800/1511827200

Sold for 9 Keys

https://backpack.tf/profiles/76561198149175706#!/compare/1510358400/1510704000

Sold for 9 Keys

https://backpack.tf/profiles/76561197961279983#!/compare/1509148800/1509235200

Sold for ~9.5 Keys in Items

https://backpack.tf/profiles/76561198080658092#!/compare/1510876800/1510963200

Sold for an Australium Pro KS SMG(~8 Keys) and a Pro KS Shooting Star(~5 Keys)(~13 Keys total, Outlier)

https://backpack.tf/profiles/76561198271577665#!/compare/1510963200/1511136000

9-10.