You might first want to solicit opinions in the Coins forum on it's grading potential. There are some knowledgeable posters there that don't frequent this forum. In particular, CoinKid has a very good handle on the process as he will be working for one of the TPG services starting this summer. The pictures you supplied should be fine.
I didn't look at the enlarged photos until this morning. The thumbnails in the thread body was more than enough for "High Fives". As I look closer, especially the reverse, I have reservations if the coin is authentic. The red flags that aroused my suspicion is the joining of the letters in Half Dol. and "Unit" in United. I'm no expert on counterfeit fakes so I won't dismiss it as such. For now, you have a heck of a find.
I viewed the enlarged photos to detect signs of cleaning. Sadly, at some point in it's lifetime, it has been cleaned indicated by the striations in the field caused by rubbing and the dirty halos around the stars and lettering. I didn't want you to send it off to PCGS only for it to be returned ungraded. NGC would still grade it.