You can't just go off of WMS.. Pinion offset and bearing style is just as important. Small axle bearings should be avoided. Cougars Mustangs some early Broncos are close to the correct width but all have small bearing ends.
Like i said before late model trucks and vans are the best junkyard options to start with. But to get the pinion offset right you cant just take equal amounts off each side
The Lincoln Versailles is a good option. They have big bearing axles, the pinion offset is close. They have disc brakes. The width is about 2" short but that wouldnt be a big deal. The Only thing you need to remember is you must hook up and use the parking brake. If you dont the calipers will not stay adjusted.