He doubles as Chance Cars who sell a range of people movers. Almost every vehicle sold at there yard has a)1/2" white walls on the tyres, and random vinyl on the side.
I don't know if they do any bigger than 10mm, but he has a machine that does it properly.
With real white wall tyres, BG World Wheels are a NZ wholesaler for white wall/lettering tyres. Pretty much do every oldschool tyre out there. But they cost mega $$$. I can price but the flappers would be a MUCH cheaper option and are reusable.
Check out this catalogue from there website to get an idea on what they do.
-Chris