The cross reference current number is 012068. Its a 7 3/4 X 6 1/2 3 blade OMC pin drive. Near as I can tell, I believe its a power prop for a mid 60’s to late 70’s 6hp J/E, possibly a sailboat or other heavy boat that the standard 2 blade can’t handle.
If you have too many, AND not enough, you're a collector.