I would think if you have different combinations of dice to use in a game (e.g., a single 6-sided die and also two, six-sided dice), you would have TWO symbolic dice devices (borrowing from the same graphics for the pip faces). You would actually do the same thing to have multiple die roll buttons (unanimated).
That would use a bit of space on your menu bar, so it might be worth it to eschew that and just set it up to report the random die roll in the log buffer…
see the demo mod inside zip. You want something similar. This should get you on your way how to do it. this demo was posted a long time ago somewhere else but not sure where in forums. Might try searching for stuff on symbolic dice to see other various discussions