There are more sales than just this.

1. http://www.tf2outpost.com/trade/23667304 Traded this + ~1.4 keys for Kill-a-watt Infernal Impaler(2.18 buds * 0.9 = 2 buds) + Dead Presidents Birdcage(~1.4 buds outdated. Current seller selling birdcage at 1 bud http://www.tf2outpost.com/trade/24560127) . Probably ~2.8 buds

Backpack of seller

http://backpack.tf/profiles/76561198071286877?time=1417043322 After

Backpack of buyer

http://backpack.tf/profiles/76561198061508957?time=1416988800 After

2. http://www.tf2outpost.com/trade/23884728 Sold for Haunted Phantasm Jr Bolted Biccorne(Not priced) + 3 keys + ~6.4 keys in sweets

CUrrent sellers for the biccorne http://www.tf2outpost.com/trade/24629360 2.5 buds.

3. http://www.tf2outpost.com/trade/23981952 b/o 3 buds

To summarize,

Judging from all those, i don't see how this hat will be worth more than 3 buds. Your sale is also pretty outdated now compared to those that I have presented which are more recent. Please do resuggest at a more appropriate range after doing a more thorough research on the sales that I have presented with proper mini suggestions done. Thanks!