You can't have a GTG on a non-slabbed coin. You can ask for opinions, but how can I guess the grade if it isn't already graded?
I don't see any luster based on the photos. I'd grade it AU Details but it's hard to tell with those pics.
From the angle it looks like the top two diamonds are missing or worn, there also is some weird coloring on the shield on the reverse. If the diamonds are missing won't grade higher then AU.
From the angle of the pictures and the color of the coin I would say it would come back as questionable color. It reminds me of one that was whizzed. It has some nice details,but I also wonder if that is a scratch across the shield(or is it just a stain). In any case I would call it AU-details.
It "could." Come on, shiny, you've been here long enough, what's with the lopsided shots? You know we need them straight on to grade them. Only tilt them like that when you're wanting to capture color that won't capture straight on. We can give you some good advice. You just have to go first, and give us what we need.