I have a 1980 CJ7 that I've had for about 2 months. At some point someone swapped Dana 44 axles under it, both front and rear. This was a big reason why I was interested in this Jeep. The PO didn't know what vehicle the axles came from.
What I did was I brought the brake pads into our local auto parts store and we looked up all the vehicles that had a Dana 44 front axle in the 1970s and 1980s. It looks like my axles came from a 1/2ton Ford truck from the early 1980s.
If you do this go to a decent auto parts store, not Autozone, O'Reily's, etc. Look for the guys behind the counter with grey hair that have sold parts for decades. They will help you figure it out. I put the pads from my Jeep on the counter and the two guys behind it knew what they came off of by looking. We confirmed it by matching them to a new set if pads. They were right the first time. They looked up other vehicles to be sure but we didn't didn't need to do that in the end.