I've used Midwest Camera repair for all my Nikon gear, bodies and lenses, routine and not so routine issues. They're excellent, affordable, fast and an authorized Nikon repair service. PLUS they give free estimates online here http://www.midwestcamera.com/estimate.html which are realistic and accurate.

Here's their home page. http://www.midwestcamera.com/index.html

Personally, I'd much prefer an authorized repair service CLA any of my F bodies or AI lenses before buying another used one from someone. Reason being I'm not really positive about what I'd be getting and as we know, there is no such thing as a good time for camera failure.
Take it light
Mark