Yodobashi Camera and Multimedia is about 1 block west of Yokohama Station and will have what you need. I have no idea of the directions from your hotel but the concierge should be able to direct you, or you could just take a cab and direct the driver to "Yodobashi Kamera." He will get you there. Take the old unit to show a clerk.

From your difficult to understand post, it may be that you have already tried Yodobashi but I can't tell for sure. If so, did you show the old unit to a clerk. In my experience, Yodobashi has EVERYTHING electronic. Perhaps they didn't understand what you needed.

If Yodobashi doesn't work out, the next best would be Bic Camera Yokohama-nishiguchi, which is just to the southwest of Yokohama Station, just across the canal. It is about 2 blocks south of Yodobashi.

Maps to both of the above are easy to find on Google Maps. Just google "Yodobashi Camera Yokohama map" or "Bic Camera Yokohamanishiguchi map."