I think you'll find the cost of rebuilding almost equals the cost of new (aftermarket). I did.
Whatever choice you make, ensure that the shop knows this is a LandCruiser torque converter; there are a large number of similar Toyota T/Cs, using the same housing, from the same family, but don't have the same internal parts. They'll all fit, but that's not the criteria for success. For example, Precision lists the same T/C for over a dozen Toyota transmissions, from as many years, as "fitting". If it were a Camry to an Avalon, or a Tundra to a Sequoia, I wouldn't be concerned, but it's not.
If someone can definitively state they know (and not from reading several "well documented" posts) the T/Cs used in the LandCruisers are compatible, in funciton, not form, with other models and years, I'd like to know about it. It would be nice to have a (operating) spec sheet for the 80 series T/Cs.