Early fraternity badges were made by local jewelers.

You could find a jeweler who does custom design and have small pins made. If your college/university has an art department there may be a student or faculty member who makes jewelry.

AGDAlum

If they're looking for a budget item, though, I can't imagine they have the money to design a custom piece and a die to make multiple copies of that piece, though.

And again... GAMMA is a national organization that anyone can join. If they wanted their members to have pins or badges, don't you think they would make them?