An off the shelf exhuast for a DC5R/S won't fit onto a Base.
If you are going to buy an off the shelf item, make sure that the exhuast you buy is made for a base DC5.
If I was in your situation, I would just go to an exhuast shop and tell them you want a 2 1/4' cat back exhuast with a cannon on the end. It'll be cheaper and easier then importing something that might not fit.
Fit the Injen yourself. There is going to be countless DIY's on the interwebz... just google "Fitting Injen Intake onto DC5"
