I know you are seeking local sources but just in case, here is a link to a company we recently ordered barn door hardware from. They deal in Coburn hardware which is made in the U.K. and seems to be well engineered stuff. The price was about 2/3 that of comparable systems quoted by barndoorhardware.com
We looked for an AZ dealer for this sort of thing and were not successful. I went so far as to team up with a horse fanatic coworker who was building a stable at the time and she ended up going with mail order as well. I'm sure there is a company out there, we just couldn't find them. Best of luck to you on your search!