Note: Sales go in order from newest to oldest

Sellers below 1 key:

http://www.tf2outpost.com/trade/15422066 - 5 ref

http://www.tf2outpost.com/trade/15421953 - 3 ref

http://www.tf2outpost.com/trade/15421870 - 3.66

http://www.tf2outpost.com/trade/15421803 - 5 ref

http://www.tf2outpost.com/trade/15421432 - 4 Ref (sold)

http://www.tf2outpost.com/trade/15420988 - 5 ref (sold)

http://www.tf2outpost.com/trade/15420543 - 3 Ref (sold)

http://www.tf2outpost.com/trade/15420503 - 4 ref

http://www.tf2outpost.com/trade/15419142 - 6 ref (sold)

http://www.tf2outpost.com/trade/15419140 + Exorcism for 5 ref (~4.33)

http://www.tf2outpost.com/trade/15418929 - 3.66

http://www.tf2outpost.com/trade/15418668 - 4 ref

http://www.tf2outpost.com/trade/15418266 - 5 ref (sold)

http://www.tf2outpost.com/trade/15417998 - 5 ref

http://www.tf2outpost.com/trade/15417873 - 5 ref (sold)

http://www.tf2outpost.com/trade/15417565 - 4 ref (sold)

http://www.tf2outpost.com/trade/15417394 - 3 ref (sold)

http://www.tf2outpost.com/trade/15417244 - 4 ref

http://www.tf2outpost.com/trade/15417045 - 4.66 (sold)

http://www.tf2outpost.com/trade/15416486 - 3 ref (sold)

http://www.tf2outpost.com/trade/15416478 - 5.33

http://www.tf2outpost.com/trade/15416428 - 3 ref (sold)

http://www.tf2outpost.com/trade/15416297 - 5 ref

http://www.tf2outpost.com/trade/15416174 - 4 ref (sold)

http://tf2tp.com/trade.php?trade=9867850 - 2.66 (sold)

Bought below 1 key:

http://www.tf2outpost.com/trade/15413253 - 2 ref

http://www.tf2outpost.com/trade/15394072 - 0.55 o.o

I would say 3-5 ref would be a good range.