I have a set of the Stelling green headers and they had also developed a leak around the 4 tube collector area. I called Stellings and they said they did not repair them anymore but sent them to a guy locally that did all the repairs for them as he was cheaper than what they could repair them for. They gave me his # and I sent them to him. To put a completely new collector, pressure test, and polish my header was $450. I think the guy charged $50 and hour and he said the most expensive repair he has had to do was replace the collector. Header came back looking brand new.