There are quite some similar specimens of this type of Hunting Volley Rifles known, most of them still mounted on their original painted two wheel carriages.
The one from the Krakau National Museum that Michal kindly posted here

(first image below) is one of the very few fired by means of a wheel lock mechanism while most surviving samples, their number of rifled barrels ranging from 7-9, use the more advanced but still contemporary flintlock.
The bunch of barrels of some of the flintlock specimen are signed by their maker,
Valtin (sic! for Valentin)
Muth à Zerbst, East Germany. One signed seven barrel example, the back sight missing, was sold from the Franconian armory of the Counts Schenk von Stauffenberg, Sotheby's, July 10, 2002 (see scans below).
Best,
Michael