M22 lower

[Brambo]

I have a lower that stamped m22 REH IND out of marysville ca. It came with there version of the bullet button. It's round not oval like the radlocks or bullet buttons. The magazine catch was there own design, and the weak link that snapped. Anyone know if I can get a replacement for these lowers before I mill it into a working lower? I don't want to mill it because the round hole is slightly bigger then the oval of a regular mag release. It's going to have a slight gap after I mill it. Any ideas on this company and if parts can be ordered would be helpful.