Well, the Super Cub gear legs have square brake attach plates, with ever so slightly different bolt hole angles. Better for Grove brakes if you want the calipers aft. But yes, totally interchangeable. And if you are experimental, some of the repro parts are better than the PMA parts, and lots less expensive. Opinion.
The one with no brake provisions is likely for the lower gross weight. Unless you have a method to verify that the tubes are all the same dimensions you should leave it on the wall for conversation purposes. I knew an old timer who had one of those no brake Cubs.