I was in the market for such a truck about 6 years ago. I have had 69 Camaros forever and my wife wanted a classic for her to drive. We did not want a restored pickup, because you cannot drive them like we intended. I found a 51 chev 3100 that the owner had already done the Mustang II disc IFS (R&P power steering), V8 and a 76 trans-am disc rear. The body and cab were disasembled but 80% there. Picked it up and parked it. Now it time to get working on it.
Future plans are 383 chev with tremec 5 speed, but stock looking. Keeping the bench seat, but adding new 3 point seat belts.
So I would recommend finding a stalled project with IFS and other things you want and finish the build your way. Rusty stock trucks are what I see out there, but it would be lots of work to modernize.
