Since I actually have one of these hats, I keep an eye on the value from time to time. The only one on the market just sold for a HOUWAR + 13 keys. The buyer is now trying to flip it for a profit.

http://www.tf2outpost.com/trade/4977562 (trade where it sold. scroll to bottom to see seller disclose price it sold for)

http://www.tf2items.com/id/reds77?time=1349875505 (backpack history showing level 28 HOUWAR gifted from the buyer)

BTW, mine is NOT for sale, so I ask that people do NOT add me to try and buy it. The answer will be "no".