You just need a pair for the odd 4th wheel and then you will be sitting pretty with an extra spare rear. In any event, those MAs shouldn't be too hard to find.

Btw, I have one old Wolber Aspin in the rear matched with a (red label) GL330. They are extremely similar in appearance, but it drives me nuts just the same. I doubt I could tell a performance difference. Still, I'm tempted to cover the Wolber decal with a matching GL330 label, and I'm always on the lookout for a 32H hoop like this: