Pelican parts forum is the one for this. I have an 87 911 and I bought a Sachs clutch on Ebay for $100, and a pilot guide bearing for the clutch also pretty inexpensively. I had to have engine dropped any way for a valve guide rebuild, but I want to say its probably 6-7 hours of labor to drop it and reinstall engine- possibly ten hours total to do the clutch and drop/replace engine. It would probably be about 900-1200 dollars (parts AND labor for the clutch) I would guess at most shops, but that is just a guess.

There are several "while you are in there" $7 dollar oil seals that I also recommend replacing at this time, they are extremely easy to replace and pretty much impossible to get to once the engine is put back in the car. I had my mechanic replace ALL of these seals and parts and labor for that part was only about $250. One of mine near the pilot guide bearing was leaking pretty bad before replacement of the clutch and I didn't know it.

I have so far (2.5 years since top end work) a completely dry engine and garage floor. That's pretty unusual for a 911. Knock on wood!

A great book to buy is "100 projects for your 911" by the Pelican Parts guru/owner. Its has helped me save alot of money by learning to do some of these jobs myself. I can and have done most of the repairs on many of my cars and stop short of DIY when we are talking about valve jobs/internal engine components.

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1991 300D 2.5 turbo
1991 560 SEL
1987 911
Toyota landcruiser
Atlanta, Gawga