6 month old price, surprisingly easy to mine the data on these sales

SALES:

Offered on (and sold for) a Blizzardy Storm Big Country (~20) and 2 keys = 22 keys

http://www.tf2outpost.com/trade/19030734

Offered on (and sold for) A Steaming Salty Dog ~22 keys

http://www.tf2outpost.com/trade/18304689

25 keys, probably pushing the boundary for relevance based on how long ago it happened but I already have other sales only slightly below this and a B/O to help substantiate this sale in the current market

http://www.tf2outpost.com/trade/17112258

B/O:

http://www.tf2outpost.com/trade/18942792 - 25 keys, 4 days old