Parts question

[cevgunner]

How do, all;

I have a Bushmaster BAR308, uses the FAL mags , and came with that dippy ambidextrous mag release.  Problem is , it's sticky, hard to release the mag from either side, and RRA won't respond to confirm or deny if their parts for the LAR-8 are interchangeable.  I'm not about to blow $100 plus shipping on something that I can't send back.

Visually, the two rifles are alike.  I don't have an original manual ( bought the rifle used) , like the platform, but would like a few spares, and want to have the ability to get new parts if my tinkering goes awry.

Any thoughts?

Thanks,

cevgunner