The coin does appear to have some wear. I agree with the AU at best opinion. The color is also off. This might just be the pic, but a pinkish hue on a gold coin can be the sign of a dip. The rim ding might also keep it out of a slab. I would not send this one in for grading. It is a beautiful coin, but not enough return to get her slabbed.
Here is a quarter eagle of mine also from 1899 in a PCGS 64 slab as a comp for what the slab companies are looking for in a MS gold.