The number plates on Olga now are not plastic, they're aluminium with riveted on plastic digits.
I think the original owner fitted reflective plates as a modernising upgrade early in the car's life.
The later holiday photo, with the reflective plate, was taken in the very early 70s.
The front plate is damaged, so as a temporary measure to get her legal and mot'd, I have ordered some cheap pressed black plates from eBay. Eventually I will fit the riveted type, but as yet I haven't decided whether to go for black or reflective
J