Okay, assuming that the local pots will fit, I don't think that the total tonal character will change. Just the "taper" or how the wah responds to your step. Syempre mawawala yung scratches and the other things that make you want to change the pot in the first place. Like if you replace the pot with a log taper where a linear taper is required, the "wah" action will happen near the end of the step. Pero kung sa pwede, pwede. Ok, that assumes that there is a physical "fit" ha and you can transplant the gear on the old pot to the new one.
Okay...try cedist.com, I think I saw pots for various wah pedals there. They're a wholesaler though, but they have a sister company that sells retail, just click on that link when you find it.