Yup, Tom, should be fatty enough if the brisket is of decent quality and not trimmed.
Dan, Safeway isn't a butcher's shop, it's a store with a meat department with employees. A butcher would have no issue with grinding your meat for you. 
Though I prefer a meat grinder you can use a processor. Cube the meat, partially freeze, 'grind' in smaller quantities till halfway there, periodically scraping down the sides of the bowl, partially freeze again, finish in small quantities in the same way, till the texture you seek. A grinder is easier but a processor works.