7 months old price.

Sales :

http://backpack.tf/profiles/76561198119574760?time=1428649200

http://backpack.tf/profiles/76561198119574760?time=1428994800

http://www.tf2outpost.com/trade/24867066

Sold for a strange pro machina (~16 keys) + some painted hats (~2 keys).

A total of ~18 keys.

http://backpack.tf/profiles/76561198095280456?time=1426057200#page1 - before

http://backpack.tf/profiles/76561198095280456?time=1426230000 - after

Sold for a smoking regg.

A total of ~17 keys (the guy who sold the regg for the modest also had a C/O of 17 pure and a B/O of 19 http://www.tf2outpost.com/trade/25156640 )

http://backpack.tf/profiles/76561198095280456?time=1426402800 - before

http://backpack.tf/profiles/76561198095280456?time=1427439600 - after

Sold for a steaming swatter.

A total of 12 keys, outlier.

http://backpack.tf/profiles/76561198073756672?time=1428217200 - before

http://backpack.tf/profiles/76561198073756672?time=1428303600 - after

http://www.tf2outpost.com/trade/25506010

Sold with a duped p. fetti sack (~9.5 keys) for a morning glory bombing (35 keys) (was offered on the bombing so no overpay. The price of the bombing would usually be 37 keys, but B/O was 35 keys).

A total of ~25 keys. (rounding down)

Mini for sack :

http://www.tf2outpost.com/trade/25616592

Sold for 9-10 keys (couldn't confirm the exact amount in bp histories)

Current trades :

http://www.tf2outpost.com/trade/23479319

Was offered either a stormy tin gallon (~16 keys) and sweets or a steaming luch (old price but seems ~16-17 keys).

http://backpack.tf/classifieds/?item=Modest%20Pile%20of%20Hat&quality=5&particle=31

Classified listings :

1 seller for 23 keys, 1 for 25 keys.

Conclusion :

Current price is too high and no longer reflects the market. 3 sales ranged between 17 and 25 keys suggests it's the most appropriate range. The sales, along with current and past outpost offers as well as a few outpost quickbuyers shows that the 12 keys sale is too low.