1. Ask EMF firearms if they can offer any help http://www.emf-company.com/ . EMF used to sell a lot of ASM revolvers. I bought quite a few ASM cap and ball revolvers from them over a few years when they sold at the Big Reno Gun Show.
3. Longshot. . . try gun shows for a used cylinder. Be sure to take your ASM Remington and a dowel to check cylinder alignment. You might find another brand that works.