For stuff like this, you can sometimes just search JP Cycles-it'll give you a pretty good spread of fitment, that will cross with your bike.
My experience shows that those early 80's Sporties will used the same rear wheel as a Superglide, FX, that is in the same year range-sorry don't have something more definitive for you-do some Googling-or check out Drag Specialties to cross your fitment as well. Best of luck-
Justen