your integra needs a header, not headerS. And as for the exhaust, If you want to keep an oem style muffler, find a jdm ITR muffler and get an exhaust shop to run stainless piping from the cat to the muffler. don't forget a resonator as well.
OR:
get a WS2 muffler by itself and get a shop to fab up a custom catback for your car. As long as you use a resonator and a real cat (not a test pipe) it will stay pretty quiet.
EDIT: just saw where you said it was for an altima. your name is MKIII, your sig pic is a teg, but you drive an altima?
forget the ITR muffler and go with a WS2 or greddy SP2.