There's a guy on eBay who sells all kinds of coool auto decals, and better than stock quality. His seller name is r_gravley
Here's a link to his store online-- Gravley Merchandise If he doesn't have anything, eBay is still your best bet!
Even for parts, check eBay. Or alternately, write to the manufacturer and request replacements--lots of them are very helpful is fulfilling requests and orders for defective kits,