if you bought it for 23, you shouldnt suggest 20-30. Also, there have been other sales:

Sold with searing furlined for planets bomber:

http://backpack.tf/profiles/76561198059551935?time=1439928839 before

http://backpack.tf/profiles/76561198059551935?time=1439967600 after

probably an outlier

Sold for 23 keys (your sale)

http://backpack.tf/profiles/76561198124241068?time=1440132248 before

http://backpack.tf/profiles/76561198124241068?time=1440140400 after

-> 23 keys

Sold (again) with searing furlined for duped black max (~30 at that time)

http://www.tf2outpost.com/trade/26814988 "offered", and seemingly quicksold

http://backpack.tf/profiles/76561197991688774?time=1439819225 before

http://backpack.tf/profiles/76561197991688774?time=1439881200 after

Sold for haunted ghosts noble??

http://backpack.tf/profiles/76561198095902384?time=1434178800 before

http://backpack.tf/profiles/76561198095902384?time=1434286818 after

histories match

Noble: http://backpack.tf/item/645178215

Shako: http://backpack.tf/item/3394113192

As for now, 23 is the only sensible sale.

Honestly, Id wait for more sales on this, as the sales are all over the place here. Given the three first sales, Id say its safe to assume the noble sale is an outlier, since the guy eventually QSed with another hat for a max (clearly showing the buyer valued it lower).

Given the ease at which it sold for 23 pure and the nature of the max sale, it is clear that the bomber sale and the max sale should be outliers as well (as they would end up pricing the hat at 8-13)