Super looking paint job, Crash.

25ft lengths of wire? Sounds like an Allparts purchase, as I recently bought the same quantities of the same wire.

Other sources of tubing (if you can wait a few days for delivery) is eBay or Amazon. The PVC tubing doesn't expand much, maybe only 1mm maximum, so it needs to be just smaller than the pot shaft diameter. You can heat it to make it more pliable, but it then becomes harder to push on. So you might want to consider searching for latex surgical tubing, which comes in different sizes, but is more flexible and stretchier than PVC. It's also what's often used as mounting springs on Fender pickups.