There is a driver backrest made by Protac. Ma Kawi makes the Fire and Steel extended sissybar, and there are pics on Knifemakers sig line of a sissy bar and pad he made. Watch ebay for the first two. There is a direct ebay link at the bottom of the forum list. They show up on there occasionally.

 

also you can get the extended backrest through Kawasaki's web sight or the stealership...the protact driver's back rest can be found HERE... Corbin also makes a back rest as well for the driver..unfortunately you have to buy one of their seats as well
**NOTE** drivers backrests can not be used while carrying a passenger.