I stumbled across these Gustav Tichy of Moravska Ostrava(Mährisch Ostrau) longarm images. I believe he gave Lovena a run for their money or Gustav Tichy & Lovena sourced the same craftsmen for their sidelock examples.
I'm leaning that the falling block was sourced from the craftsmen at Zella-Mehlis.
Falling block with some interesting text on the right side of the tube
The owner/seller gave that the O/U had a 1958 date on it, if I read it correctly. But this O/U passed thru the Zella-Mehlis proofhouse more than likely during WWI or shortly thereafter. So just from these few examples it seems that Gustav Tichy had a pretty solid sourcing line to the craftsmen at Zella-Mehlis.
Anyone have any Gustav Tichy examples or info? He passed thru Frantisek Faukner's shop as a journeyman.