Who makes headers for the new 572 crate engine (tall deck) for 1966 and 1967 Chevelles or where can I get them made?

Other than having a chassis shop build them from scratch, your olny other choice is a place like Lemmons headers.

Still don't understand why GM would use a tall deck block with raised exhaust port heads...stupid if you ask me as now your run into header problems like your asking about.

Stahl headers would also be a place to check.
Step header will be required www.stahlheaders.com (http://www.stahlheaders.com)

Aw heck,,use exhaust manifolds,,gonna be too much power for ya anyway ;)

I run 2 1/8" Hooker Super Comps on my 540.
Not a tall deck but I can't see that really being an issue with the clearances now available on my '70.
And it does have raised port Dart Pro I heads.