Part of the premium pricing. Western’s exchange program is generally on-demand, they aren’t usually sitting on a stock of built and pickled motors. Tell them you want to exchange and they pull a serviceable core and start the process once your deposit has arrived. They build and ship the motor, then you do the swap and send back your runout motor.
Once WS gets your old motor back, they inspect the case; if it’s not repairable or you choose to buy a motor outright, there’s a $5K core charge.
Like Penn Yan, they do their own case inspections and repairs, it doesn’t go off to Divco or somebody. Old cylinders are overhauled, new Superior Milleniums are what’s used for the OH.