Hate to be a wet blanket, but they are all going to be pretty close in price, because there are only a few intakes and exhausts, and they are all competing with each other. So it's not like you're going to go to a site that has it for $75 less than everyone else.
Just go to
http://www.the370z.com/
Scroll to the very bottom, and you will see probably 20+ vendors of various products.