Tire decals

I don't know whether I'm doing a wrong search, or they just don't make them outside of the model they come with. I just finished up building and putting the decals on my Shelby GT350R and I've never had these decals like this before, 'Firestone' that are applied to the rubber tires and I love them. I'd like to get more of these, doesn't matter what brand (Firestone, Goodyear etc) but I'd love to get a few sheets of them for the models I have that don't have them with the kits. Does anyone know of a source for these? I would really appreciate it. 

Thanks

Rob