I am not sure what part of LA you live in, but there are 2 XJs with NP231s at the following salvage yard:
U Pick U Save Self Serv Auto
17800 Vermont Ave
Gardena, CA 90248
Its technically Gardena, but right next to Torrance. I was there today during lunch grabbing a seat belt from one of these and both cases are decently clean and still complete.
Not sure if this helps you out, but figured I would mention it.