Looks like this was exchanged 1:1 with the ushanka - http://www.tf2outpost.com/trade/27784937 - which had a b/o of 70. The b/o of 80 listed here was dropped to 74 before it sold.

http://backpack.tf/profiles/76561198121578764/#!/compare/1455004800/1455091200

Eh... I would probably go with 70-87 here. 70 may be a bit low, but 87 is probably high given all the b/os are running consistently under that. It's up for sale at 80 currently. And 70-87 would essentially be a refresh for this.