Conservative bump.

Sold for 1.44

http://www.tf2outpost.com/trade/20771146

http://www.tf2outpost.com/trade/20889269 (Sold the one in the trade, still have one)

Sold for 1.55

http://imgur.com/99wgDHb

Sold for 1.77

http://www.tf2outpost.com/trade/20812452

Conclusion: Before you say something stupid like "Not enough proof, downvote", take a look on the market first. This thing is so rare now. Demand > Supply because supply of craft hats went down and it's reasonable for this thing to rise.

Feel free to counter / support my proofs.