Hello, and welcome to CoinTalk! I would call that a heavily worn 1943 Walking Liberty Half Dollar, no error.
Well, the reverse could have been strruck through grease / weak strike then worn down in circulation. Could also have been ground down or just heavy circulation wear that somehow shows on the reverse more than the obverse. Either way, in the condition it's in it doesn't carry a premium, IMO.
Wow, that is the most worn reverse I've ever seen on a Walker with any kind of decent obverse. Usually, but not always, the front and back are about evenly worn.
That is why I think it was done on purpose with a lap or flat sanding top. These coins are/were often made this way to attach to front of money (bill) holder /clip , Ornamental belts, and such, front of a leather hat band etc. I have done this to some Large Mexican coins for vacquero holsters. A flat surface makes it much easier to attach them.
