I´ve seen examples of them in print but I can´t remember where. They look late medieval or Renaissance.
The pics come from "das Zeugbuch des Kaisers Maximilian I. 1475"
Digital Version HERE
Look under the titel (left Hand side ) Messinghakenbüchsen
The book shows a whole range of arquebus´s, big, small, on Trestles, two legged stands, wheels, breech and muzzle loaded.
Looking at the pics...the "Flaming Brands" depicted on the RedBox Bods now makes sense.
Arquebus from The German Hakenbuchse..a Hand gun with a hook so it can be braced when being fired.
And...at PSR they are sceptical about the kneeling bod using a pick axe to chip shot down to size but..what is pictured in the bottom left Hand Corner of the pic below?
Number 4 is labelled as an Archer..but he´s Holding a crossbow and has a quiver Holding bolts..not arrows
It could be RedBox were being too literal (or not) by portraying a hammer with two spiked heads but the pic below ..the one on the right has, when viewed from the side, what Looks like two Points. Even though they aren´t as common these days, so called "Stone Dressing Hammers" used to be common and they do (did) look a wee bit like small pick axes.
It´s a Stone cleaving axe, something like...HERE.
IMHO, definately not a tool for shaping shot of the size that would pass through any of the holes in his board but maybe for cutting bigger chunks of Stone into a rough size.
And just to confirm...here´s a site listing, among other Stone mason Tools, axes (plain edged) and Hand picks (Sculptors pick)
The Art of Making in Antiquity