5 month old price!

Sale 1:

Sold with 16 keys for Australium Sniper Rifle (33) = 17 keys (B/O caps it at 16 keys)

http://www.tf2outpost.com/trade/27287344

http://backpack.tf/profiles/76561198031371895?time=1445929200 (October 27th)

http://backpack.tf/profiles/76561198031371895?time=1446015600 (October 28th)

http://backpack.tf/profiles/76561198031371895?time=1446015600&compare=1445929200

http://i.imgur.com/UrsEeJU.png

Sale 2:

Unable to identify sale

[no outpost trade]

http://backpack.tf/profiles/76561198142979486?time=1443510000 (September 29th)

http://backpack.tf/profiles/76561198142979486?time=1446015600 (October 28th)

http://backpack.tf/profiles/76561198142979486?time=1443510000&compare=1446015600

Sale 3:

Involved in a bulk deal for Cloud 9 Jumper's Jeepcap

http://i.imgur.com/2I8w3Js.png

Notes:

Only one sale is valid out of the three most recent ones.

http://www.tf2outpost.com/trade/27287344 - B/O of 16 keys

http://www.tf2outpost.com/trade/27228780 - B/O of 17 keys

Conclusion:

One valid sale at 16 keys. Taking a final value of 16 keys.

Feel free to support/counter my suggestion!