Mutie weapons are rather hard to come by and to be honest even in the original models it was unclear which ones were which. However whilst browsing Forgeworld’s new releases list we found these:
The Volkite Caliver Set (Found under Horus Heresy if they move it in time). They’re far from cheap but apparently that’s what Imperial calivers look like. The rules for them can be found on page 65 of Digganob.