As suggested by blind polar bear

http://www.tf2outpost.com/trade/12357728 (3 keys willing buyer not sold?)

http://www.tf2outpost.com/trade/13442054 (3 keys, 5 days) willing buyer not sold?

http://www.tf2outpost.com/trade/13572631 (3.5 keys, >12 hrs)

http://www.tf2outpost.com/trade/13593972 (3.5 keys, 8 hrs)

http://www.tf2outpost.com/trade/13517261 (low end but lists as 4.5?)

http://www.tf2outpost.com/trade/13033760 (4 keys w/ dominations & revenges, 2 weeks)

http://www.tf2outpost.com/trade/13544431 (4 keys w/ snipers & engis killed, 2 days)

http://www.tf2outpost.com/trade/12431197 (4 keys, 1 month)

http://www.tf2outpost.com/trade/12676998 (4 keys, 4 weeks)

http://www.tf2outpost.com/trade/13190845 (4 keys, 2 weeks)

http://www.tf2outpost.com/trade/13364117 (4 keys, 1 week)

http://www.tf2outpost.com/trade/13566419 (4 keys, 1 day)

http://www.tf2outpost.com/trade/13559899 (4 keys, 1 day)

http://www.tf2outpost.com/trade/13573292 (4 keys, 1 day)