It is not easy to find these unless you want to pay a lot for a complete set. I had the plate but no numbers. They are very used but they will look the part and I only need to show 0 and 4 plus the upper retainer plate, the rest file in the back to fill the gap in the pins. Some people put the year of the truck, I might do 52.
Examples of bridge plates on M37s:
Some jokers here with the 69