This is the response I received from the seller a couple days ago:

There is an S mint mark. I do not think it would be proof condition, as it appears there is either a scratch of some type or misprint on the heart where the shiny silver shines through. It honestly looks like it was made that way though. Also the outside gold edge is kind of darkening. Maybe it cleans? Do not know though, as I am not a coin person. After really looking closely, I do not there are some very fine, hard to see scratches, but not soemthing that shoots out at you.