I found a company that makes headers for a 3cyl engine.  Its for a turbo charger, but I'm not sure which model.  I'm guessing its for the 660cc not the 550cc, but they might use the same headers.  Also, it is from a very old catalog, so the company may not make it anymore. Oh yeah, check out the price on that thing too. 59,800 yen!! Not exactly cheap

