I recently found an incredibly odd quarter when searching through my coins. It is a 1973 D Washington quarter in a reasonably well preserved condition. However the letter 'R' is engraved on Washington's head. Now I've scoured the internet to try and identify this quarter, but so far I've found no match. This leads me to believe I'm in possession of an extremely rare quarter. Ill attach images. I just need help identifying and getting the possible worth of this quarter. Thanks!