I've seen new Colt 22 AR conversion in the package on gunbroker for $200 to $300. I'm surprised the Colt conversions have been holding their value considering the limited supply of magazines. CCS had a batch of firing pins and extractors made and now BDM has manufactured the billet high capacity mag and a polymer high capacity mag in the works. I traded for a Colt kit a few years ago since I had a couple of DPMS dedicated uppers which use a magazine which will work with the Colt conversion. This was prior to the BDM high capacity mags becoming available. Personally I like the design of the Atchisson/Ciener/CMMG/Spikes design better. If the kit shows a lot of use I'd probably try to get $175 to $200 and if new in the package $200 to $250. My Colt kit is reliable but the mags and parts are cheaper for other brands of conversion kits.