SAN DIEGO — San Diego officials are exploring several new potential revenue streams for the cash-strapped city, including more parking meters, a rental car business tax and parking fees for nonresidents at beaches, Balboa Park and Mission Bay Park. Other potential sources of new cash for the city are higher parking citation fines, new fees to launch boats, allowing more advertising in tourist areas and a new tax on parking garages. A 25-page analysis of these options recently released by the city’s independent budget analyst says the most feasible options are boosting parking meter revenue and…