Oh well
You are right about the one piece pipe. I've called several dearlers and parts supply places and it looks like no one makes a pipe and silencer with spark arrestor for this bike.
One place I talked to Dennis Kirk said they had an FMF that would work. So I ordered it, and after receiving it (very different) I called back and they said they had a computer issue and it actually does not fit an 03 KX60. It's a turbine core 2 and its sitting in the garage now. With some creative adaptation the local muffler shop thinks they can cut off the stock silencer and attach this one in its place. I made a drawing of an adaptor piece and achine one out to fit over the OD of each pipe. The new one will stick out a little further after installed but should clear the back tire and side guards. Anyone ever custon fitted a turbine core 2 to a KX60?
Of course we could just ride at an alternative destination next weekend, but it should would be nice to be able to take my son to some of the good riding around here controlled by the USFS.