3 month old price!

Sale 1:

Sold for 26 keys

[no outpost trade]

http://backpack.tf/profiles/76561197961085576?time=1437978591 (July 26th)

http://backpack.tf/profiles/76561197961085576?time=1437980400 (July 27th)

Sale 2:

Sold on SCM

http://www.tf2outpost.com/trade/26603311

http://backpack.tf/profiles/76561198085342984?time=1437634800 (July 23rd)

http://backpack.tf/profiles/76561198085342984?time=1438915164 (August 6th)

Sale 3:

Sold for Clean Max's Head = ~32 keys (B/O was 30 keys)

http://www.tf2outpost.com/trade/26731534 | http://www.tf2outpost.com/trade/26691195

http://i.imgur.com/aZLc96G.png

Sale 4:

Involved in a bulk deal for Vivid Plasma Blighted Beak

http://www.tf2outpost.com/trade/26632749

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

Sale 5:

Sold for 30 keys

http://www.tf2outpost.com/trade/26544771

http://backpack.tf/profiles/76561198065201997?time=1437548400 (July 22nd)

http://backpack.tf/profiles/76561198065201997?time=1437634800 (July 23rd)

Conclusion:

Three valid sales at 26, 30 and 30 keys. Taking a final range of 26-30 keys.

Feel free to support/counter my suggestion!