http://www.tf2outpost.com/trade/19749424 offer max head + 1 bud 4.1 seems to have sold for a max + keys

http://www.tf2outpost.com/trade/19843306 sold his stash + secret rack for a poisoned shadow exe 19.1 - 12.9 = 6.2 x 0.9 ? = 5.5 ? (seems to have been outlier)

http://tinypic.com/view.php?pic=mr70x3&s=8#.U1ykEfmSySp 5 buds from previous suggestion ? maybe valid now

http://www.tf2outpost.com/trade/19847577 stash sold for 4.6 pure

Rack mini suggestion

seems to have offers of 13 -15.7 http://www.tf2outpost.com/trade/19843306

Others on the market seem to want 4.1 buds - 6.5 buds