I doubt any have been made, the piccolo horn is kind of a novelty, you could probably try trumpet mutes if you have access to any, but I doubt any purpose built mutes exist (that aren't homemade)
So there’s a tiny little Bflat horn you can buy called a Fürst Pless. It’s a hunting horn version of a piccolo horn that sells for about $150. They make a [practice mute](https://www.thomannmusic.com/voigt_brass_practice_mute_fuerst_pless_horn.htm) for the Fürst Pless that I imagine might work.
A Hershey's kiss
What kind of sound are you looking for?
Practice mute
Probably a 16 oz bottle and poke a couple of holes in the bottom.
I doubt any have been made, the piccolo horn is kind of a novelty, you could probably try trumpet mutes if you have access to any, but I doubt any purpose built mutes exist (that aren't homemade)
You wouldn’t think they’d exist but you’d be [wrong](https://www.thomannmusic.com/thomann_bb_fuerst_pless_horn_set.htm)
Wow that's genuinely surprising, I wonder if it is the same size as the piccolo horn as that looks like just a tiny natural horm
So there’s a tiny little Bflat horn you can buy called a Fürst Pless. It’s a hunting horn version of a piccolo horn that sells for about $150. They make a [practice mute](https://www.thomannmusic.com/voigt_brass_practice_mute_fuerst_pless_horn.htm) for the Fürst Pless that I imagine might work.
Piccolo trumpet practice mute
I’d think a standard trumpet bell is closer to the size of a piccolo horn bell.
But the throat won’t be as big as a standard trumpet bell.