Started this to help out Google, then he closed his suggestion D:

Sales:

http://www.tf2outpost.com/trade/20894284 QS for 5.5 pure (Ignoring)

http://www.tf2outpost.com/trade/21667019 Offered + 3 keys for scorching softcap = 6.4 buds

http://www.tf2outpost.com/trade/21698635 Sold for clean scorching spartan + 3 keys pure = 6.5 buds

Others:

http://www.tf2outpost.com/trade/21296726 Sold for duped burning spartan + 24 keys = 7 buds**

**He sold the burning spartan for 6 pure: http://www.tf2outpost.com/trade/21299203

http://www.tf2outpost.com/trade/20714763 - DUPED

Sold for a Arcane Towering piller of hats - 7 * 0.9 = 6.3 Buds. (credit slobro, prev. suggestion)

From Google #10,000 ref (prev. suggestion)

http://www.tf2outpost.com/trade/21726270 - Sold for Knifestorm Bicorne (6.3, price suggestion) + 15 bread boxes. I valued them at 3 keys a piece. 15 x 3 = 45 keys/2.3 buds. 6.3 (hat price) + 2.3 (bread boxes) = 8.6 x 0.9 = ~7.7

Sales at 6.3-7.7 rounding everything off to 6.5-7.5

(Future reference, buds are 19.5 keys)