I've searched so dont come at me tellin me to search.

First of all, Ive looked into it n sum people say I could fit an EX header on my Non vtec but Ima need to get a cat also. Then I see someone saying ima need to swap out my whole exhaust system to put the ex header on my dx model. ived searched around to find the exact same headers that are on my car right now but cant find em anywhere. will the EX headers fit on my 97 DX hatchback with only adding the cat or do i need the whole exhaust replaced?