Depending on which SeaDoo you have, SeaDoo sells the tower in a kit that bolts on to the back of the 4-tech hulls. It is the same as they have on their Wakeboard edition boats.
I had to edit this as I just found an online aftermarket source
http://leadgroupinc.com/SpotNTow.php
if the link doesn't work do an online search for Spot-N-Tow
I had to edit this as I just found an online aftermarket source
http://leadgroupinc.com/SpotNTow.php
if the link doesn't work do an online search for Spot-N-Tow