I painted my SSG69 stock with Alumahyde II Parkerizing Grey, that looks more like a dark green, but im ok with it.

Should I final coat with Matte Clear or just leave it as is ? Im wondering if the Matte Clear would give it more of a finished look.

I wouldn't, but lots of people will disagree with me.

I would not as well, AH isn't like Kylon that is easily affected by cleaning agents and oils.  Plus most clears end up making the object more glossy even the satin ones, not a look I would want on a field rifle.

Share your paint work, post a picture OP. I used some of their dark park finish about a week or so ago and it does indeed have a hue of something grayish/greenish in it, sorta like it.