You are supposed to replace the expansion valve and dryer with a new compressor because in cases of the compressor itself E36 M3ting the bed, the system will be full of trash, this is not your case by the sounds of it.
I'd just bolt in a new compressor w/ appropriate oil charge, vacuum it down for an hour, charge and go. Buy a new compressor from the OE supplier.
Did this exact same replacement (clutch died, Subaru, etc) several years ago. New compressor worked fine for at least two years.
When the a/c quit the second time, shop thought it was the expansion valve. 
Sold the car. Problem solved. 
The two occurrences were not directly related though. I've replaced many bad compressors and never put a valve in. Never seemed to be a problem.
I used to sell ac wholesale. I strongly recommend you change the expansion valve. They are cheap and can gum up your system. In other words, I wouldn't risk your new compressor over a $3 part.
Did the clutch fail or the pulley bearing? You mention both and they are two different things. If the clutch failed there is no reason to replace the expansion valve. If it was the bearing, then you may or may not need to replace the expansion valve, depending on whether or not metal shavings were introduced into the refrigerant system.
Since we're talking about AC in here, I have a question, so I'm going to thread jack. I have a compressor and lines and an entire AC system that's been open for a while. The compressor had tape over it, but it fell off at some point. It still pumps air when I turn it over by hand if that means anything at all.
What would I need to do to put this together as a working AC system? The accumulator and expansion valve, plus all of the seals I can get to are the obvious things, but what can I do about the compressor? Everything looks clean from what I can see, but that means dick when you can't see more than half an inch into a complex machine. I have no problem with a rebuild, if I could find a rebuild kit. Is flushing it and hoping for the best an alright decision in this scenario? The compressor did come off of a working system, but that was 7 or 8 years ago.
In reply to Derick Freese:
If it still has oil in it, it may be okay. Or not. Depending on the application and how much it's worth to you, you could drain the oil, refill it and install it. It's a risk, but if it's been stored reasonably well it's probably okay.
I figure the most I'd be out is another expansion valve and accumulator if it is bad, right? Compressor still seems to have plenty of leftover oil. I think I'll make a new thread later.
For a system that's been open more that a few hours your better off to pump an purge several times where you pump down then fill with N2 let it sit 20 minutes or more pull vacuum and refill do this several times as N2 is dry and will pull out the moisture better then just pulling the system down as some water may not make it out but freeze in place under to strong of a vacuum. If you have concerns there might be a leak fill system with 80% N2 then "top off" with refrigerant and sniff with the heated pentode probe like a ZX-1.
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