I got mine from Discount Van Truck, LTD, 800-414-0485, Item code #11363, $159.95 plus tax and shipping, $197.15 total. Bolts to seat and floor without raising the seat. Took me about 30 minutes. Works fine.
The only caution is in routing the airbag sensor wire. It's almost too short. At some point I will splice in an extra 6" of lead so I don't worry about breaking the wire when I swivel the seat.
When you remove the factory base lift the carpet and re-direct the wire to the rear of the base then mount the swivel base. Then set the seat onto the swivel base and tighten down and reconnect the wire to the seat.
If you don't do this the airbag is effectively disabled.
2016 MBZ Sprinter 144" 4wd.
07 BMW 525xi wagon