Just wondering what you guys think I could get for this?

The tacked on barrel nut has been removed, and I also have a refinished stock off of a Romy G for it. Only problem is, its a single stack as seen. I have less than 200 rounds through it. And never had a problem w/ it. I know you can get them now for $500, so somewhere around $400 maybe? I'm planning on building another AR, and already have another ak, and some sks's in x39. Plus I haven't shot this in almost 4 months.