Grymster, I believe this will prove cheaper than buying the gun and cartridge cylinder separately:
http://www.taylorsfirearms.com/produ...Conversion.tpl
I bought my Uberti 1858 from Taylor's a few months back, and I can attest to both their service and price.
When I get around to buying a cartridge-firing gun, one of their 1858s in .38 spl will be on my list.
J.C.