I faced this exact same dilemma when restoring my grandfather’s old farm truck three years ago. Purists always advocate keeping original parts, but finding obsolete vintage gears can turn into an absolute nightmare during a rebuild.
However, going through with a certified gearbox repair ended up preserving the authentic driving feel and maintained the truck’s overall collector value significantly better than a modern swap ever could.
If keeping the vehicle original matters to you, paying the extra cost to rebuild the factory drivetrain is definitely worth it. I highly recommend sticking with a original gearbox repair.