Two retailers in Southern California have reached a $55 million deal to buy Phoenix-based Pro's Ranch Markets, which filed for Chapter 11 bankruptcy protection last May, the Associated Press reported yesterday. The family-owned chain of grocery stores popular with Latino customers was founded 31 years ago and has seven stores in Arizona and two each in New Mexico and Texas. Cardenas Northgate Group Ranch announced yesterday that as part of the deal, it will also get Pro's Ranch Markets' corporate office and a 151,000-square-foot warehouse in Phoenix. CNG Ranch officials say all 11 Pro's Ranch Market stores will remain open for the foreseeable future. Cardenas Markets currently owns 26 stores in California and three in Nevada while Northgate Gonzalez Markets operates 38 California locations.