276 or 294 any case

Buy a 741 case and diff locally. Then you can easily have a set of 2.94 gears shipped in from anywhere in the country and it won't break the bank.

Then build it locally or yourself because you will want to have new bearings in it and a fresh setup for longevity.

40 year old rear chunks need to be gone through, bearings rust and wear, seals wear out and leak, differential gears and cross pins wear resulting in a rear end that will clunk and not last long.