You can't. The GC component cable has some custom chip in it, so there are no 3rd party cables that I know of. I know Monster won't make them because the cost of reverse engineering the chip would make the cable cost twice as much as the Xbox/PS2 cables.
I would suggest some sort of extension cable, I guess.
I really think you're incorrect. It's not shown on Monster's site, and I've never seen one in a store or anything. Plus the info above came from a friend who works at Monster.