You're going to have a difficult time, if you're able at all, to find any 7-passenger vehicles with automatic transmissions. The reason is fairly simple, the benefits of driving a transmission simply aren't as relevant to the segment of the market 7-passenger vehicles are meant to serve.
Even in Europe, where manual transmissions prevail over automatics, 7-passenger vehicles are virtually (if not actually) nonexistent. On the other hand, some vehicles, like the 2010 Ford Flex (up to 7 passengers) and Lincoln MKT (seats 6) now offer automatic transmissions with "manual" modes that allow the driver to change gears using steering wheel-mounted "paddle" shifters.
I hope this helps!