Hey,
Don't be afraid of the blind packs - you can actually tell which figure is in them by their coding.
I looked on Ebay and this one is quite affordable - Kre-O Transformers KREON MICRO-CHANGERS 2-in-1 Complete Preview Set of 6 New
http://r.ebay.com/ZyzP68
It contains all 6 figures and costs about $30 - so $5 each which I think is reasonable.
I ordered a set from them and got all 6 figures.
The codes are written on the packs:
Crankstart - A1010 (214510)
Galvatron - A1008 (214518)
Scorponok - A1011 (214511)
Spinister - A1007 (214517)
Sunstorm - A1009 (214519)
Waspinator - A1012 (214512)