Your state may be a pain in the @ss on this. I know I went to a wrecking yard localy, and found a set of perfect (note, not near perfect...PERFECT) 1970 Ohio plates. When I went to the counter, they would not give them to me.
He said it was illegal to sell them, so I said I would relieve him of them for no cost, but pay full price for the parts I was getting. (I always chew them to the bottom price, and they know I will) He said no, took the plates, and cut them in 1/2 on the spot.
Some states will not let you get vintage tags.
even just for show reasons.