Stainless steel six cylinder headers. The inlet pipes are 1-5/8" and the outlet is three bolt with a 2.5" pipe. Be aware the outlet flanges are welded at a slight angle (see pictures) and the pipes overall are the short style, so they'll need extensions to mate to a muffler. But this means you could have the three bolt flanges on the extension pipe welded at an angle to compensate and make the pipe come out straight, plus then you can get flanges to match your muffler.
Asking $550 plus shipping.