From memory: no. They can only mix up to their database, which is proprietary to every vehicle manufacturer. RAL codes are standard in stuff like industrial design and construction.
Unfortunately you'll also find that the person mixing the paint is usually a spotty kid who doesn't know any more about paints than the average Joe on the street!
You can buy RAL paints from paint suppliers, though, or even on ebay. You might not be able to find a touch-up can but you should be able to find a small tin of spraypaint - just spray some into the lid and use a paper matchstick to dot it on.