Firebird Central has a good selection. 1967-68 Firebird master cylinder Rock Auto doesn't carry the Firebird master, but does carry the Camaro version. A little cheaper, but I know the Camaro disc calipers were just a bit smaller than the Firebird's. That may be why they don't have the Firebird ones. I have several sets of each and you can see the difference with your bare eyes.
