Someone mentioned exhaust manifolds (or headers).
Pacemaker are the only people who are doing them for LHD applications to the best of my knowledge.
They also happen to be good quality; test right up there with the best and can be had ceramic-coated too.
Are in 1-1/2, 1-5/8 and 1-3/4" ....Tri-Y and 4-into-1
If anyone's interested I've got their details (in Oz).