I recently acquired this pipe and it is beleived to fit a 94-01 klx250/300. it has 040103 stamped on the mounting bracket. Looking for some insight, thanks. It may also be for sale for the right price, used very little if not at all.

 

That might actually work on a 250S, I'm looking at this pic and wondering if yours might have an interference with the airbox, but then again it does seem to curve down and then in which could avoid that problem. The Q4 in the picture is pretty long, so it is angled down and the pipe section of it does not have the S-bend that yours does.