Last time a friend had a clutch put in it cost about $550. That was for a 2WD Dakota. Most of that is labor, getting the tranny out and back in. The parts were only about $125 or so. He had them replace the pressure plate, clutch disk and throwout bearing. All of those parts usually come in the clutch kit since it's a good idea to replace them all at the same time.
Depending on condition, the flywheel may need to be resurfaced or replaced but only if it's in really bad shape.
On my K20, the flywheel was glazed and had been overheated many times so I had to get a new flywheel. I forget what I paid for it but it was in the neighborhood of $100-150 (though I could be wrong).