Welcome,
I agree with Antonis - you won't find a 100K/25K pot anywhere. Pot manufacturers will make you such a thing if you're willing to order 100,000 units, but otherwise forget it. That suits Boss for their pedals maybe, but doesn't leave the rest of us with many options.
Your options are to either re-design the tone circuit to use the same value as the volume part (or vice versa) or to parallel up another resistor to adjust the value like Antonis suggested.