1) Sold for 400 pure plus Pugilists protector knifestorm

Screenies/History and supporting mini's below. Credit to previous suggestion

Screenie: https://imgur.com/a/JfpBidU

Compare: https://backpack.tf/profiles/76561198210673328#!/compare/NaN/1658361600

History: https://backpack.tf/item/2045879881

Mini for Pug sale 1: https://backpack.tf/profiles/76561198339336870#!/compare/1660176000/1660262400 - seems to be same price range

Mini for Pug sale 2: https://backpack.tf/profiles/76561198045749377#!/compare/1660176000/1660262400

https://backpack.tf/profiles/76561198339336870#!/compare/1660176000/1660262400 - This was the Harvest Moon (250) + Unusualifier (~12) + 106 keys = 368

https://backpack.tf/profiles/76561198056793885#!/compare/1659484800/1659571200 - This supports

So the Demonflame Private Eye sold for Pug (368) + 400 keys = 768 keys = ~ 770 keys

2) 900 keys

History: https://backpack.tf/item/2045879881

Seller: https://backpack.tf/profiles/76561198210673328#!/compare/1667260800/1667692800

Buyer:

https://backpack.tf/profiles/76561197991154117#!/compare/1667692800/1667865600

Going 770 - 900 or an average of 835 keys