There's probably a kiosk at your local mall where you can have all the stickers you need made. Just bring them a jpeg of the logo and they can digitize it, then print out what you need.
For swag, you want to hit up the next MOD (Mitsubishi Owner's Day). These are held yearly in Chicago and Cypress (it's worth the drive).
http://www.mitsubishicars.com/MMNA/jsp/owners/mod.do