You might want to talk to Bill at American Powertrain. I don't know if they can help you because they primarily deal with Tremecs. They did some great work for me on flywheel, clutch, etc. Since I have a 360 that is externally balanced it was really hard to find the right parts. Bill had their billet shop cut me a steel flywheel to solve my problem.
Added: If you decide to talk to him tell him I sent you and you want a good deal. He gave me some really good prices considering what they did for me. And no, I don't get anything for sending him people. I think he just felt sorry for me because of my experience with another compay (nobody around here).
Jim