Old price is 6 months old.

Sold:

Hat + 1.5 keys were traded for FN Woodland Warrior RL (20 keys) + 1.6 keys. This sale can be rounded to the hat being traded for 20 keys for the sake of neatness. http://backpack.tf/profiles/76561198116682136#!/compare/1466899200/1467417600

The only other hat on the market has been unsold for 8+ months and the seller has given no indication of how much he wants for it nor has he recieved any offers. http://www.tf2outpost.com/trade/28179420 & http://www.tf2outpost.com/trade/27920953

Unsold for 3 months with B/O at 23 keys: http://www.tf2outpost.com/trade/28294717

As such with a unsold hat for 3 months at a B/O of 23 I can not see any value above 23 keys being appropriate for the hat. Using the sale listed above for 20 keys as proof I am suggesting a new price of 20 keys. I believe only one sale is sufficient to adjust the price of a hat that sells so infrequently and has very few of it available on the market.