Your master cylinder is most likely a brembo. It will be the same a lot of Ducati (monster, multistrada, super sport), and aprilia's (from 125's to rsv's). They come in black, silver and gold. The color does'nt make them better (just the look). The only difference comes from the piston diameter. It will make it sharper, stronger, more user friendly depending on the size, but for your trial bike, I think any will work well.
Franck