I'm looking for an cable (adapter or something) that can connect a
4-pin mini-DIN S-Video out

to a:
HDMI in

The reason being I have an ancient piece of specialized equipment (no it's not a DVD- player) that only outputs to S-Video (4-pin) and the modern display only accepts HDMI input. By the way, this is not a home theater question.
So far I've only managed to obtain a 7-pin mini-DIN S-Video out to HDMI in.
Does anyone know where to get a 4-pin mini-DIN S-Video out to HDMI in cable (if there's such a thing)?