AC clutch or compressor???

This is copied from my thread over at YotaTech and in the Tacoma forum

'97 4runner, auto, 4wd, SR5, 3.4L. I headed out Friday on 1.5 hour ride when I left, the A/C was COLD as a always. When I got close to my destination, I noticed it was NOT quite as cool. On the way home it became obvious that the A/C was no longer cooling. It may have been a bad idea, but I stopped by O'Reilly and got a DIY can of 134. It didn't make any difference and the system didn't wasn't to take it in. After getting home and running the truck with A/C running wide open I watched the compressor. What I found was that the A/C clutch would occasionally engage, but with all sorts of wailing and gnashing of teeth. It was NOT rotating freely and the belt would actually start to smoke. When this happened it would only last a few seconds and then the clutch would disengage and things were normal until the clutch engaged again. When engaged, the pulley WOULD rotate, but not smoothly. My question is this. Does it ever happen that only the clutch will fail w/o the compressor failing or is it more likely that the compressor is dying and the belt just doesn't have the torque to turn a compressor that's on it's way out? I'm anything but an A/C expert, but I do have access to vacuum pumps and any tools to do the mechanical work. At 306,000 miles it's hard to justify spending big money on a repair. I've had very good luck with buying used OE parts from eBay. Most of the sellers show the vehicle with VIN and odometer #'s. Most parts have come with lengthy warranties. I know there are REAL experts here. Assuming I have competent help, is there a reason NOT to work on this myself. As it's NOT working now, I'm not sure I have much to lose. I have the ability to recover refrigerant as well. Thanks in advance!

 

Compressor.....sounds like.