Selling/sold for 5 keys:

http://www.tf2outpost.com/trade/10343913

http://www.tf2outpost.com/trade/10341628

http://www.tf2outpost.com/trade/10326011

http://www.tf2outpost.com/trade/10317470

http://www.tf2outpost.com/trade/10312308

http://www.tf2outpost.com/trade/10308569

Selling for a little over 5 keys:

http://www.tf2outpost.com/trade/10344099 - 5 keys, 1 ref

http://www.tf2outpost.com/trade/10316697 - 5 keys, 2 ref

http://www.tf2outpost.com/trade/10317238 - 5 keys, 2 ref

http://www.tf2outpost.com/trade/10311429 - 5 keys, 3 ref

http://www.tf2outpost.com/trade/10309556 - 5 keys, 3.66 ref

http://www.tf2outpost.com/trade/10305347 - 5 keys, 3.66 ref

Unsold

http://www.tf2outpost.com/trade/10341236 - 6 keys, unsold

http://www.tf2outpost.com/trade/10309947 - offers of 5 keys

http://www.tf2outpost.com/trade/10153274 - offers of 5 keys

http://www.tf2outpost.com/trade/10343203 - offers of 5 keys

http://www.tf2outpost.com/trade/10340893 - 6 keys, unsold

http://www.tf2outpost.com/trade/10339183 - 6 keys, unsold

http://www.tf2outpost.com/trade/9953682 - 8 keys, unsold

http://www.tf2outpost.com/trade/10283476 - selling for 7, offers of 5

http://www.tf2outpost.com/trade/9944236 - selling for 7, offers of 5, Unsold

http://www.tf2outpost.com/trade/10160030 - selling for 7? Unsold

http://www.tf2outpost.com/trade/10281568 - selling for ~6 keys (gen. Archimedes), unsold

http://www.tf2outpost.com/trade/10263422 - selling for 7, offers of 5, unsold

http://www.tf2outpost.com/trade/10235811 - selling for 7, offers of 5, unsold

http://www.tf2outpost.com/trade/10254471 - (recent) offers of 5, unsold

http://www.tf2outpost.com/trade/10258412 - selling for 7, most recent offer of 5, unsold

http://www.tf2outpost.com/trade/10253720 - selling for 8, unsold, offer of 5

http://www.tf2outpost.com/trade/10239430 - selling for 6, unsold, offer of 5

http://www.tf2outpost.com/trade/10126392 - selling for 10, offers of 5

It seems that they aren't selling at 6 keys anymore, I believe that the high end needs a slight drop.