if you wanna get really technical about it, on a full size car if stock is called an exhaust manifold. it is only when you get a performance exhaust manifold is it called a header which is classified by seperate runners per cylinder and joining at the collector instead of there being only one true runner.
none the less i know what you meant and in this case exhaust manifold and header pipe are one in the same which no matter what terminology is used, is easily distinguishable from a tuned pipe or muffler