Stock headers for CB550s are a dime a dozen -- it's the mufflers that rot out. That being said, sounds like you are looking for a 4-1. You won't be able to use the CB550F Supersport header due to peg and brake and kicker clearance. Others are around, Kerker e.g., or you might want to write to folks selling whole sets if they'll just sell the headers, including Carpy. I guess it also depends on your budget...