I called Advantage Battery this morning and they will sell them for $12.00 each, they are located at 312 N Rockwell in OKC, Im only picking up about 4 of them, so there will be plenty left. The AH ratings for the C&D UPS 12-310FR is 85Ah, 95Ah for the 370's and I'm not sure on the 390's. The 310's weigh 67lbs and the 370's weigh 82lbs, again I dont know about the 390's.