It's all in the shape of the 9, come on didn't you know that? Seriously that coin has been more than altered. @Jack D. Young
OK, obverse "19", S-43. Image courtesy PCGS CoinFacts; 1st is the subject example: 2nd is a non-doctored or corroded example: Doesn't "look right" due to the noted and obvious re-engraving of the hair; beyond that I am not sure of the question?
Between the engraving and PMD, the horeshoe curl I usually look for along with the lack of a lowest curl for quick ID is altered just enough to look odd. It reminded me of the poor early counterfeits at first, probably from the engraved hair. But it has other diagnostics indicating it started as an authentic specimen or was a higher grade transfer. I've already confessed to not knowing how to ID those.
I always try to look extra close at Obverses 8 and 19 because each has two common pairings and two NC pairings. Interestingly, I have three of the rarer 11/12/17 pairings and neither common.