Notoriuz
You definitely have options. Unfortunately, I don't know a whole lot about Nissans (I consider myself a Honda/Acura guy), but you can check out
www.nopi.com, where there are lots of goodies available for tons of import sedans, from intakes to body kits to suspension components (and probaby for domestics as well).
A good source for suspension parts is
www.show.com, with some of the best pricing on the internet.
And be sure to look at
www.stillen.com as Igor suggested. They definitely make turbos, intercoolers, and related items for Nissan applications.
I'll post again tomorrow if I am able to find more information to help you out. Good luck with your search, take it easy Richard-
-JD