Roundel Lights?

Hello all.
Can anyone tell me the proper name for the lights that are used on some older race cars to illuminate the number? I’ve done countless web searches and can’t find anyone who sells them. Guy on the phone at summit racing didn’t have a clue what I was on about. They look sorta like license plate lights, but I’m sure are more powerful.
Doug use the search function in the top right corner , part numbers and how to modify the lights can be found. Some very good stuff.