Can Anyone Identify This Vintage Taillight?

Hey guys, just picked up this cool tiny taillight from a buddy last night and was wondering if anyone can tell me what it's from. It's too cool not to run so it'll end up on my Triumph or Shovel, but I always like to know exactly where all the parts on my bikes originated. I've never seen one this small with the clear lens accomodation for the license plate light. The red brake lens is the same size as a quarter and has a "jewel" shape to it on the inside that shows up when the light turns on. It's got a really cool hinge feature that swings upen to access the light bulb. It's got 3 factory rivets that hold it onto the stamped steel bracket. Obviously, I'll be removing the rivets and the big bracket, but I thought that might help identify where it came from originally. A gold star goes to anyone who can help, THANKS!