[DonRotolo]

12/10000 of an amp is a very small current indeed, circuits will be happy there.

12/1000 of an amp is getting close to the limits of what the circuit can deliver, but with little or no additional load you'll be OK. Certainly a 1k pot will be fine for testing, and a 10k pot will provide (about) the same voltage per degree, so you can swap one in some later time with little or no changes to the software.