Found this...
http://mcm.newark.com/NewarkWebComme...KU=24-7835&N=4
I'd worry about signal loss with something like that though. S-video is dependent on proper termination, a y-cable isn't going to do that for you. You're much better off with something like
this that will properly terminate the signal. (there are tons of those out there, just do a search for "s-video splitter"