Trouble with NOS is the O, they are still 60 odd years old. Have to say I'd now go for the relining route. As Pastparts point out, because it came off your vehicle and they dont alter the outside, you KNOW it's the right one and fits. If the master is beibng done, might you not consider doing teh wheel cylinders as well? So often new master more presure wheel cylinders give up. Get the lot done at once, new synthetic fluid and cupro nickel pipe, forget, it's going to be the great great great grand kids problem.