Here is the 1875 S/S graded ANACS AU50. The Breen reference is #3875. The coin is also identified as having a misplaced digit. The top of the 7 is allegedly struck into the denticles. I saw another S/S recently and it was also an MPD. Maybe they all are? Breen did not mention the MPD in his description. In this photo you can see a litle disturbance in the denticles right under the 7.
Here is the reverse, my digital camera cannot focus on the mint mark too well, I have to experiment with it some more. This pic is not focused too well.