Looking on the internet for the Roland R-Bus cable RBC-1, RBC-3 or RBC-5?
Finally found them and then looking for air because of the prices…happened to me also.
Then I found the pinout of VS-planet and decided to create one myself. I bought a 2nd hand DB25 cable and two breakout boxes male pins.
In one hour I had my own working R-Bus cable for only 20€ 🙂
Here the pinout which you will need! I created in Excel my own list based on the colours of my cable. Of course you can select any color as long a you connect the correct numbers. (link to the original post from 2003 – http://bit.ly/2ovlVF6)
Good luck on rolling your own cable!