I'm in Canada so I don't know what $500 buys down there. But you should be able to get a pretty decent flat screen I would imagine. My preference would be to Sony, Panasonic or Toshiba but JVC, especially the I'Art wouldn't be bad either.
As for connections, you should be fine with S-Video. Don't know which JVC receiver you have but it probably does S-Video switching, in which case you would run your S-Video from both sources into the receiver and S-Video from the monitor out on the receiver to the TV. Also, of course, you are going to run audio from both sources into the receiver.
As for connections, you should be fine with S-Video. Don't know which JVC receiver you have but it probably does S-Video switching, in which case you would run your S-Video from both sources into the receiver and S-Video from the monitor out on the receiver to the TV. Also, of course, you are going to run audio from both sources into the receiver.