This has never been sent in but it probably needs to come out of the Dansco. I would think the staining/toning would hold it back a bit.
I think this series is the hardest to grade. That being said in my completely amateur opinion XF45, but you are far smarter than I am.
I would say 35/40 and a candidate for conservation. I’ve seen coins like this with some help end up with a nice even brown look that will be glossy post-conservation but still grade.
I think that the color will hold it back. In the old days, it would have been a VF-35 or so. If the color were even, it would be at least EF-45, maybe AU if there were some mint luster in the protected devices. I was shocked with this came back from NGC graded AU-58 20 years ago.
I'm thinking it looks better in hand. With that being said I believe it could be AU low to mid-range. Nice coin thanks for sharing, good luck.
I've noticed a significant loosening of TPG grading standards for the 1877 IHC. They give this key date a pass on conditions that would result in a details grade for other dates. They also upgrade by at least one grade and I've seen coins in holders that were, IMO, three grades higher than they should have been. That said, this example would probably straight-grade at XF-45. I say that while acknowledging and agreeing with previous posters reservations.