If you have the wrecked wing, it shouldn't be hard to take it apart, or get the broken bits together enough to get something that looks like an origional rib. Since the wing is straight, you shouldn't have any trouble kocking out a pile of copies using the broken one as a pattern.

Edit: I forgot to add: It's a trainer. Keep the LE fairly blunt, and avoid warps, and frankly, you don't have to be exactly on. A little variation here or there in the exact airfoil shape won't matter in the air. It ain't rocket science