Yes, that's the one I was suggesting, although with the shipping it's kind of pricey.
One thing I just thought of, which has come up recently so I should have considered it right away, is that the older Yamaha keyboards apparently use MIDI Active Sensing, which can cause problems if you're trying to use them as MIDI keyboard controllers.
Basically, the keyboard is constantly sending out Active Sensing messages, sort of like "MIDI pings," and the device that's receiving the keyboard's MIDI data is supposed to send back a steady series of Active Sensing messages in response so the keyboard knows that the connection to the other device hasn't been lost. If the keyboard doesn't receive any of these "MIDI pings" back, it assumes that the connection has been lost and stops sending any more MIDI data to the other device.
If this is what's happening when you try to use the cheap interface cable, the symptom seems to be that the first key you play on the keyboard will be sent to the other device, but then the note will stop and nothing else you play on the keyboard will be sent to the other device-- at least, that's my understanding of what was happening with another member who ran into this problem.
If that is indeed what's happening, there might be a way to have the other device to send Active Sensing messages back to the keyboard, although I haven't tried it myself. The idea is to use an additional app on the computer or tablet or smartphone and have the app filter out any unwanted MIDI data (such as the Note events) coming from the keyboard and send the filtered events back to the keyboard. The only events you'd really need to send back to the keyboard are the Active Sensing messages, so if this additional app can filter out everything but the Active Sensing messages then that would be ideal.