PPL - really dont bother looking for company who has the stickers..
just get the file i linked go to the nearest adv. materials agency or garage or whatever it is, and they will cut/plot the sticker in any colour you want, and size, and quality will be perfect.
just need to find a shop where they are making stickers/signs/banners or soemthing like this... easiest, and by far the cheapest way to do the thing!