Both the standard and the alpenhorn look a little odd for an EIR Roman unit.
Musical instruments in the Roman army at that point should look like this:
Troops shown are a tubicen, with a tuba, on the right and a cornicen, with a cornu, on the left.
Which is not at all to say you can’t use the figures you have. Just be aware that “caligae counters” may look at them sideways 🙂
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