Here's some of the things I'm interested in:
http://www.diproductsinc.com/Detail.aspx?PROD=112029&CAT=3601
http://www.diproductsinc.com/Detail.aspx?PROD=186967&CAT=3603
Be Careful... if you are a non-resident of the USA but are acting as an exporter of Firearms parts the total MUST not exceed $500 (an not include barrels, receivers and /or cylinders... ITAR regulations forbid exports outside of these exceptions.