crux131
+1y
If wanting to keep the truck 6 lug, look at:
ford courier/Mazda b2000 pre 86
Datsun/Nissan 620 or 720 rears would probably work.
Toyota 4x4 pre 89/90, whenever they changed body styles.
Maybe an older Pup or Chevy LUV.
84 or 85 and down plymouth arrows/mitsubishi pickups.
I am not sure what width you are looking for, but the courier swaps are good for a few inches on a post 86 mazda. If wanting to go 5 lug, I think the toyota 2wd is really the only rear. Unless you want to pull the axles and have them redrilled.
Best bet, got to a junkyard with a tape measure and a buddy. check all the small truck rears available and go from there. Remember that you will need to get the matching driveshaft yoke for whatever rear you chose, and have a driveshaft made.