Hmm.

Sold for a Blizzardy Storm Pyromancer's Mask(56.5 Keys, rounding to 57)

http://backpack.tf/profiles/76561198044333971#!/compare/1463011200/1463097600

Sold for a Demonflame Bone Dome(57 Keys) and a Strange Pro KS C.A.P.P.E.R(~15 Keys)(72 Keys total)(B/O was 65)

http://backpack.tf/profiles/76561198123097664#!/compare/1462492800/1462579200

http://www.tf2outpost.com/trade/28110819

Sold for an Australium Pro KS Black Box(~26 Keys) and an Australium Spec KS Wrench(~26 Keys)(52 Keys total)

http://backpack.tf/profiles/76561198084976847#!/compare/1463184000/1463270400

Sales seem to fit, 52-65 Keys should be fine.

Additional Proof/Counter-Proof/Constructive Criticism/Feedback is always appreciated.