Well im a Ford technician and it would take me probably 45 minutes to pull the trans (or at least separate it enough from the engine), 10 minutes to change the bearing, 30 minutes to reinstall the trans, and 20 minutes to bleed the system. So the dealer would probably charge you 3 or 4 hours of labor plus the throwout bearing (maybe $30? Just an educated guess). My delaer charges about $100 an hour for labor. Other places are normally around $80 an hour. So probably between $300-$450 depending on where you go
If your throwout bearing is on the way out, then there's a good chance that the rest of the clutch is likely past it as well. You may want to replace the pressure plate and the disc as well. Around here the going rate for something like that around $500-$600 for labor at most independent shops where I live (VA). Plus the cost of the part.
Brian, how exactly do you "bleed the system" on a car with a mechanical clutch?
I replaced my TOB on my 91 GT in about 2 hours. That is having to drop my H-pipe exhaust and taking my time. It isn't that hard to do. It is much easier with two people and a good jack to lower the tranny. Just make sure the input shaft is out of the engine completely before lowering. You'll know when it is too. As far as the cost, I would figure about 75-100 to have someone else do it. A shop will have a lift which will greatly speed things up, but they always drag it out a couple hours.