I had an air powered lumbar support installed on my driver's seat in Red Bay, AL, but I would think there shops all over the country that can do it.
In my case the installer laid the seat back all the way flat, opened the bottom of the upholstery, inserted an air bladder, and closed the opening. He then installed a small 12V pump under the seat connecting it to the incoming seat adjustment power source, and installed an inflate and deflate switch on the side of the seat next to the other seat controls. Works like a charm.