There's a junkyard about 10 minutes up the road from me that i visited about 10 times when i first got my new XJ... called "Ted's Auto Parts" in plumsteadville, PA. The owner himself is a jeeper, owned an '89 XJ (sold me his locking rear box, rear cargo area hard plastic cover thingy, cupholders, and visors for like $20 bucks). he now owns a '94 GC (sorry, rambling...) but anyways he has at least 4 XJ's in the yard as well. I distinctly remember his old XJ having power door locks when i yanked all those goodies out of it...
Teds Auto Parts - 215.766.8180; wouldn't hurt to give him a call.