I'm pretty sure that this is the N-4 die marriage which is a very common variety. It's hard to tell when coins are well circulated.
As far as grade I will give this coin an F-12 market grade and net grade it down to EAC 8 because of the rough surface. By net grading the coin I'm basically saying that while the coin has F-12 sharpness I'm only willing to pay VG-8 money for it.
1849 N-4 R.1 12/8