One of the reasons we don't see some of the guns & rifles listed in the catalog is that they were made in very limited numbers, such as full stock single barrels. Another reason is some were made for other vendors. Once I bought a Drilling marked by a famous Munich gun shop and only found its real parentage afterwards when I examined it at home - it was/is the Merkel model 143 as shown on page 39 of this catalog. I have a number od Ferlach and other Drillings but this one stands out easily.

Cheers,
Jani