A better question might be "who cares?" Or maybe I should say, "why do you care?" You've replaced it so it's not original. Rebuilders have a habit of mixing parts, so it might be a conglomerate, anyhow. Unless you are worried about "restore correct" next time it fails put a modern PM starter on there
"In general" there were at least two "motor lengths" (the length of the motor proper" which indicates lighter or heavier duty. Earlier starters did not have the little ears sticking out the sides of the solenoid with the screws in them. I've forgotten, but this was supposed to be an improvement. The big no1 issue with working with old Mopar starters is "not" forgetting to detach the solenoid wire that is wire wrapped or soldered into the starter when disassembling the thing
