That model number is I believe the same model number as the tube used in NEC XV 29 plus Presentation monitors.
The NEC can do up to 800x600 VGA, as well as take a 15Khz signal. However, its quite possible the 15Khz signal is scan/line doubled up by NEC electronics. So in fact I would guess its basically a PC monitor that can do 30Khz to 50Khz. (ie anything up 800x600)
I could be wrong though, so you may want to check. I have no idea what the "Video Converter IO" 9pin is on the back.