Hi Roy,
I can't see you having much luck locating AMT Stock parts, they are long gone. However, I'm sure Dark International and Armco could help you out with a aftermarket set.
Good luck with the Hardballer, the QC on them was a little uneven. Seems people either get good ones or very, very bad ones.
Make sure to grease the rails, the AMT were the first Stainless Steel 1911 and used the same material for the upper and frame. Galling was pretty common.