Imagine AT&T Park flanked by giant shipping cranes - that's pretty much the vision A's boosters have for a 38,000-seat ballpark at the Port of Oakland, just west of Jack London Square. The $500 million waterfront ballpark is being proposed by a team led by Clorox chairman and CEO Don Knauss and former Dreyer's Grand Ice Cream boss T. Gary Rogers - with the blessing of Oakland Mayor Jean Quan. "It's one of the two sites we promised Major League Baseball we would offer, and it will be available early next year," Quan told us Friday - the other being the current Coliseum site. "Trust me, Oakland is hot now," Quan said, "and a lot of developers would love that (waterfront) site if it doesn't become a baseball stadium." The Save the A's effort also includes at least two other prominent figures, development consultant Doug Boxer (son of Sen. Barbara Boxer) and Mike Ghielmetti, whose Signature Development Group wants to turn Oakland's Brooklyn Basin into housing, retail shops and parks. The idea is to entice A's owners John Fisher and Lew Wolff to join the plan - or, failing that, to get Major League Baseball to see Oakland as a viable spot for a new ballpark and kill the A's hopes of moving to San Jose once and for all. "The group envisions itself as a caretaker during the period it takes to get the A's to come to the table," said one knowledgeable source, who asked not to be named because of the delicacy of the talks involving MLB.