ac compressor bearing noise

I've got a terrible grinding noise coming from the general vicinity of the a/c compressor on my 2000 cherokee 4.0. It isn't constant, sometimes it goes away. Other times it screams. There is a difference when i turn on the a/c and then when i just turn on the vent. There compressor pulley gets very hot and there is an odd smell. I've been told that it's probably the clutch bearing wearing out, and that when it does finally seize up i'll be stuck. My questions are: can i replace the bearing without replacing the compressor or: can i bypass the compressor pulley: or could it be something else entirely? I'm only keeping the car for a couple of months before i leave abroad and i can't afford to invest a ton of money? Also, how long do i have before it seizes. It began a couple days ago. Any and all suggestions are greatly appreciated. Thanks.

since it makes noise with the a/c on or off it has to be the bearing on the pully - this can be replaced with an compressor clutch kit and the only specialty tool you will need is pair of snap ring pliars

thanks for your help Rivguy, but now there's another problem. I got the clutch plate off and removed the shim and snap ring, but now i can't get the pulley off the compressor. it looks like there was major damage to the pulley bearing. there are only half of the ball bearings remaining inside. I think all the heat and rust has fused the pieces together. the compressor spindle spins smoothly so i dont' think the compressor is necessarily bad. Can i buy a new compressor "cap" (i don't know what it's really called, but it's the black piece that holds the pulley and bolts onto the silver compressor body,) or should I just spray some liquid wrench behind the pulley and bang away with hammer?

Thanks again.