The Star Model A-Super was made in 9mm Largo,,
the Star Model B-Super was made in 9mm Luger.

On the bottom of the grip frame just to the rear of the magazine well should be either an 'A" or a 'B'. The letters denoting the Model of the pistol,,at least when it left the factory.
Ser# may also be there. It is on the Model A & B,, A&B Supers moved it to the side later
There is a difference in the Model A SUper magazine and the Model B Super magazine,,but only in the length of the feed lips at the mouth.
The B has very slightly longer feed lips to control the shorter round so it doesn't pop free of the magazine before the bullet tip has slightly entered the rear of the chamber . That captures the round and makes for more positive feeding than if using the Model A 9mm Largo mag for 9mm Luger ammo.

But many conversions have been done on Model A'super to 9mm Luger by mearly changing the bbl. Before extra aftermarket bbl were offered in the 90's for these and the Model A (9mm Largo), the easy way was to place a bushing in the front of the 9mm Largo chanber to shorten the headspace for 9mm Luger use. A 9mmLuger chamber reamer was handy to bring it to spec of course but many were done w/o one.

I don't recall if the ejectors are the same length (A & B), I think they are. Recoil springs seem to be the same. Most shooters put a new one into the older surplus guns anyway.