$25+shipping for the tank. I'll need to calculate shipping since it's kinda big. I don't know about a fuel gauge but the little round window is in good shape last I checked. Not sure if that's what you're referring to.
I'll post a photo of the window and the inside tomorrow. The inside was originally okay with a little bit of peeling varnish, but then I half-assed tried to strip it and I think I made it worse.