First unusual suggestion where I actually had to try

Sale 1:

Sold for 60 Keys Pure

BP of Seller Before Sale

http://backpack.tf/profiles/76561198035287606?time=1428103178

BP of Seller After Sale

http://backpack.tf/profiles/76561198035287606?time=1428130800

Comparison Script: http://i.imgur.com/8ILXKzt.png

Rebel - http://backpack.tf/item/3406305979

= 60 Keys

Sale 2:

Sold with a Bubbling Mongolian (8) for a TWatt Gibus (74)

BP of Seller Before Sale

http://backpack.tf/profiles/76561198075574945?time=1432632906

BP of Seller After Sale

http://backpack.tf/profiles/76561198075574945?time=1432796400

Comparison Script: http://i.imgur.com/EQrhdCW.png

Rebel - http://backpack.tf/item/3776011616 | Mongo - http://backpack.tf/item/738170142 | Gibus - http://backpack.tf/item/2273572333

Offered on so no overpay

x + 8 = 74

x = 66 Keys

Mini for Mongolian

Outpost Trade - http://www.tf2outpost.com/trade/25609899

Sold for a N&B Stuntman (~8) - Not applying overpay as 7.2 is too low

Stuntman - http://backpack.tf/item/629852211

Mongolian - http://backpack.tf/item/1613098401

Comparison Script: http://i.imgur.com/M8VpAF4.png

Conclusion:

Sale at 60 and a sale at 66, taking the range of 60-66 Keys

Feedback is appreciated :D