if you compare the red and green service-bikes, you could see that the pipes are the same. only diference are the little mods to fit to the kx-engine ..
i used an old stock-cr -pipe for my conversion , welded on the big-kx-exhaust-mount and 10mm longer at the rear section to fit right to the pc-silencer.
the service-kawasaki pipes exclusive made by fmf are very hard to get... the service-honda pipe is aftermarket: pro-circuit or fmf...