AutomasterRcbs conversion help

[Jrayecu]

I bought a progressive automasterRcbs press , new, from an auction. I shoot a lot of 338 lapua, edge, and about to start on my cheytac. I an wanting to convert my progressive press into a heavy duty single stage press. I know that I can get the shell holder adapter from midway USA but I can't find the top plate piece and rcbs said they stopped making them for a standard die just the 50 bmg now. I really don't want to spend $200 on converting it to a bmg upper then buying a bushing from ch4d. Do I have any other options?