I’m doing a .243 Win build on an Interarms Mark X action, and I’m in need of a mag follower and spring. The mag well has a spacer in the rear part to make it work for a .308-class, short-action cartridge. So I need an appropriate short-action follower and spring. Does anyone have any such Mark X, FN, Remington 798 parts available, or can you suggest a substitute that you know will work? For instance, I read that a follower and spring from a pre-64 Mod 70 might work. Thanks for your time.

Oder them from Zastava or try a follower and spring from a SA Rem 700

I used a 700 SA in mine