im friends with many of the master muralists at Precita Eyes in SF. I could easily put you in touch. A lot of these cats are graff kings too. send me a pm.
you're full of shit, i know their dope muralists up there, but they are not fucking masters, i went there as a kid and i still drop by from time to time and their graff is not that impressive.
if you're in the bay hit up
www.1amsf.com for sure, they're in contact with a lot of graff artists from back in the day, including "Twick" and others, you should consider them first and your second choice would be the "master" muralists of precita eyes...