I just got some headers off eBay. They claim to be JBA tri-y chrome. They were $229 shipped.

They fit perfect even around the clutch linkage (I have the z-bar setup) and I had them completely installed within about an hour and a half with not even one scratch. I don't know if I got lucky or what. They may turn out to be crappy, but they sure fit well and look stunning. Of course coated would probably be better for heat, but I sure like the shine.

You might want to check them out.

 

I run Mac Longtubes on our '66 and I've been very pleased with them. Good fit, no leaks.