Replacement locking bolts

I'm almost done fixing up my old 1984 Carvin v220. The last piece of the puzzle is the bolts that lock in on the headstock. I have literally no idea where to begin looking aside from contacting Carvin who told me to just buy a whole new locking clamp. Aside from their new ones screwing in to the head differently than the one that's currently on there, I was hoping to spend a couple dollars instead of $30+.

Anyone have any ideas where to find something like this?