The guns/turrets are usually missing, and yeah this ones an easy victim of yellowing, vintage prices seem to be up right now as is usually the case around a movie relase year.
There's a couple boxed versions, Yellow and blue I believe. A very simple but a great vintage piece, some of the ROTJ playsets/ships are my favs.
The vintage playsets and ships were awesome, a shame to see very few new playsets made, but it makes the vintage playsets more desireable IMO. At least they roll some ships out here and there.