PR-66. I think I can see some marks on Liberty's cheek that might knock it down to 65 but it is definitely a proof. Only 8000 business strikes and 625 proofs so a nicely valuable date.
I think those pictures are terrible and that if we had better pictures, many more people would like the coin. Interpreting the pics, I imagine this is a fairly attractive coin in hand. These pictures are designed to show the toning and not the surface quality, so I can't really guess a grade. We have no indication of the luster or the surfaces, and the low resolution and overlit quality makes it impossible to see any marks or detriments. So, I'll grade it "Has Potential."
The obverse seems to have a similar look to one of my dimes (which is, as you should suspect, a Prooflike coin):
Yeah the 1867 seated Half dime is the key... well most of the 1860's are keys to the series. Thats definitely a proof strike.