Since I've bought a dedicated Spike's upper my AF .22 kit is somewhat redundant.  It's in decent shape 2 used mags and 2 still in the foil packaging.  What would be a fair asking price for it?  Thanks guys!

You're going to get varied answers depending on the part of the world people live in. I'm in Florida there aren't too many of these kits still floating around here. I've heard of the foil wrapped mags going for 50 to 75 bucks each. The used but decent condition mags probably 25 to 35. The Conversion unit itself??? Really depends on condition, anywhere from $100.00 to 200.00 for one that's used but functional. Those prices would be a starting point. Expect that people will try to get the price down. it'll take someone who'd rather spend the money for some history rather than a conversion from Spike's, CMMG, Olympic, Ciener or whoever.

Good Luck,
Spec