Do you really need a switch, or would a DA work? If you just need to feed two monitors from one output, a distribution amplifier will do the job. Those things are everywhere now; you can even get them at Radio Shack, though of course I wouldn't trust one of those as far as I could throw it.
(Maybe that's a bad way of putting it. Those things are pretty small, and if I were pissed enough at it, I bet I could throw it pretty far.)