Apparently not all '37-D 3 leggers are created equal
This is the second I've seen. It is slabbed PCGS MS64/CAC and seems to be MUCH rarer than the fully effaced version and more closely resembles the 1936-D 3 1/2 legged coin. Apparently this die was polished more than once and this one could properly be called Die Stage A whereas the one we know and love would be the Die Stage B. The small feather directly behind the neck is completely intact on this Stage A whereas it is "detached" on Stage B.