It is an AR.. so if the trigger isn't good enough, any AR trigger would work. Same with the stock and FH.
I've been considering one of these myself. Don't have a 7.62 NATO AR.
I got a great deal a couple years ago on the $1500 SR556. Guy bought it, owned it for a few months. Put a few mags through it. Thought of something else he wanted. So he sold it "like new" to me for $950. I love AR's and didn't have a piston so figured it was worth a shot.
That rifle actually surprised me. Still does. I like it more than I expected. Now I did sink money into it to change everything over to my personal AR standard. Lots of Magpul stuff. RRA star selector. SSA-E trigger. Battle Comp MD. Etc, etc. But I ended up with a rifle that seems very, very solid. If I really did have to pick up one rifle and go fight somewhere far away, it would probably actually be my choice over all my other AR's. It isn't as light as a pencil barrel DI AR but it's accurate and never seems to have any functional issues at all. I guess it is just the Army Drill Sergeant in me, but I can't shoot a normal DI AR without cleaning it right away. Even just a few shots. Some anal part of my brain just can't live with the knowledge that there is now fouling on my bolt and BCG. But with the piston... I can shoot one or two shots and not feel bad about just tossing it back in the safe. Not an AK but I'm much more relaxed about cleaning it than I am with my other AR's.
Gregg