To me this seemed like a pretty obvious AU53, attributing a weak strike to the lack of detail on the breast feathers and hairline. Still a decent amount of luster in low points of devices and in the fields.
In terms of resale, depends who's buying it. With all the hairlines and the old cleaning a factor, it will sell on the lower end of the spectrum in my opinion. I wouldn't pay top dollar 53 money personally. If someone's buying the slab and not the coin, then maybe IMO