Thanks. It doesn't appear to be available over here unfortunately.
Ack. I missed that you were UK. Um... Crud. That RustOleum colour really is about the best inexpensive off-the-shelf match over here. The original paint job was inspired by the Candy Apple Red of the hot rods of George's youth, but washed out too light on film under the set lights, so they went with a darker shade. Ironically, what they ended up with was a dead ringer for a shade BMW introduced the following year (only a slight shade difference from their previous incarnation): BMW 138, aka Zinnoberrot (Cinnabar Red). Monofil is the UK maker I know for sure has it as a repainting/touch-up colour, including in rattlecans.. It's on the UK eBay, if no place near you has it on the shelf. I can't remember if we're allowed to post links to that site, though...
--Jonah