I'm not entirely sure how those work but I would first try unplugging the sensor and plugging it back in. More often than not a bad connection causes problems like this.
From looking at the FSM it looks like you will only be able to unplug the main power seat harness connector. The connectors for the sensors and occupant detection control module are not accessible. Still worth a shot though since there could be a poor power or ground connection in the main harness plug.
You might be able to find a used seat through Car-part.com.
It's very expensive to shop a seat though, and shipping a seat with an airbag in it presents other problems. Its an explosive, which is highly regulated, which means it costs quite a bit more. But you may be able to find a place close enough that you can just drive over to pick up the seat.
Edited by Fairtax4me, 20 September 2013 - 11:23 AM.