Larry,
I don't know how this will help you much unless you know someone in the area, but I happened to remember this. We were on our way home from Virginia last year, and we got off of I-81 near Bristol, and drove west on US 58, just north of the Tennessee line. Somewhere on that highway in a small town in the extreme southwest tip of Virginia, just east of Cumberland Gap, we stopped in a small antique store. The guy had hundreds of old Virginia license plates that had not been issued. I remember that I almost bought a set for a 57 chevy truck I had at the time. I think he wanted about $15 to $20 for a set.
If you don't know anyone in the Bristol area who could check on that for you, just look in local antique stores. I see old license plates all the time.