Worn die strike and 41 years of circulation wear. It would help if you include close-ups of where you suspect the doubling…and…did you match it at Variety Vista or Wexler? These are things you should have done before posting…it is called due diligence…jmho…Spark
With the photos you've provided, I can only see what I believe is MD on the QUARTER DOLLAR, and even that is iffy. With the rim damage, I personally would spend it. Welcome to CT BTW. Good luck on your searches.
Right or wrong, the only way to know is to post it. The answer may not be what you expected but now you know for sure. We are here to help, keep posting, good luck.