Getting Jetski

[Soccerman06]

Im currently looking for something around 4-6k, something like few year old 2001 Kawasaki 150 Ultra. I have riden that particular jetski many times over the summer cause thats what basically what I do for this summer (deliver boats/jetski to rich people, lol). I am looking for something that can do roughly +55mph on calm waters.

Any suggestions?