I have a pretty nice 34 plate. Blue with black letters/numbers. Numbers are stamped in rather than out.
I found a foot-thick stack of them the other day. All Az '31 pairs and nearly sequential at that. I'll spread 'em out and post pics later.
I have to repaint this one I have for my roadster. I also had the paint color cleared by the DMV. I took several samples in & had the girl tell which one was correct. She pulled one up on the screen & picked the color.
There are also copper historical plates to about 1977. You have to check them with a magnet though because the subsequent ones look nearly identical but are just copper plated steel. In the photo, the upper one is solid copper and the lower one copper plated. There are also some earlier copper historic plates that have black letters.