Original, ok - but when it's not working and causing performance issues, its gotta go.
Tech could try opening and repairing the pot, there are also NOS wiper tracks on the market if that would be the cause. Or you could swap out the volume with the tone pot you are using the least.
Swapping the Tone pots to the Volume and rewiring it as 50s crossed my mind. If VIPot ever come back in stock, I may consider just dropping in a new harness and preserving the originals.