I have a couple of really old 30-round AR-15 magazines that are in rough shape, with dents and splits at the seams. The followers bind. The tabs for the base plate have broken off. They are pre-ban, no less and I would like to repair them. A repair would require a new body. In order to get a new body, it is likely that the body will be date stamped. Am I wrong to assume that the law will allow me to repair my pre-ban AR-15, standard capacity magazines with new bodies? If I am correct, my repaired pre-ban magazines will have post-ban stamps. How do I prove the are repaired pre-ban magazines with new bodies?