ISO quality ground beef in Philly, a la Freida-esque blends to use at home
I'm in charge of the burgers for a party this weekend, and I want to come correct, but I don't have a grinder, and I don't necessarily feel like being high-maintenance and making up a custom blend at the butcher. Does anyone have any knowledge of good blends or simply the highest quality ground beef in Philly? Preferably Center City/S. Philly area.