I have a used set of Tein S-Tech Springs for sale as well as a Nismo Cold Air Intake both are listed on ebay.com see links below. I had these installed on an 08 Max for a little over a year they are in good condition please see pictures on ebay. If you have any questions please email me at sr20man1@hotmail.com. Thanks.

Intake Link:
http://www.ebay.com/itm/USED-NISMO-2004-2006-MAXIMA-COLD-AIR-INTAKE-16576-RNA36-/141022893691?pt=Motors_Car_Truck_Parts_Accessories&hash=item20d59e967b&vxp=mtr
Tein Springs Link:
http://www.ebay.com/itm/TEIN-S-TECH-LOWERING-SPRINGS-NISSAN-MAXIMA-04-05-06-07-08-A34-SKP62-AUB00-/141022867779?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3AMaxima&hash=item20d59e3143&vxp=mtr

 

That's a hell of a price for the Nismo intake. The springs however you can get new for about $50 more. The wear in is done though so for me that would be well worth it.