I have an '89 TriStar. and had to rebuild the swivel on the passenger side last fall. It was pretty gummed up. It's going to be hard to find a combination swivel/slide.
Is there any way you can rebuild your current swivel, or is it beyond repair?
Overtons has a swivel for $20, but you'd lose the fore/aft adjustment capability:
http://www.overtons.com/modperl/prod...l&merchID=4005