Kipplaufbüchse on Egun have probably the most

http://egun.de/market/list_items.php?mode=cat&cat=520&page=1

its also the rigth term in french http://www.naturabuy.fr/Kipplauf-cat-133.html

another keyword is Karpatenbüchse
pre WW 2 Kipplaufbüchsen are rare, this was allways a very special kind of gun and only few hunter's were realy needing this.

the new Merkel Karpathenbüchse is not my cup of tea
http://www.merkel-die-jagd.de/en/produkte/gewehre/kipplaufbuechsen-k-klasse/kipplaufbuechse-k4/

"SINGLE SHOT RIFLE K4 - FLORSTEDT‘S CARPATHIAN RIFLE

Alexander Florstedt (1863-1929) was a famous writer on hunting at the beginning of the 20th Century. The Carpathian Mountains were not only his favourite hunting grounds; he also composed the standard work on hunting in this magical mountain range in Eastern Europe. In line with his needs and according to his detailed requirements, Merkel developed the first Carpathian rifle. The current version of this traditional rifle is the K4. Its distinctive marks are the octagonal barrel and the steel receiver. The K4 thereby brings more stabilising mass to the scales – important for a steady firing position. A rifle exactly to the specifications laid down by Florstedt, an advocate of the precision single shot. The K4 is available in “Jagd” design."

but giving the rifle to another Suhl master and give it a new stock and finnish it would be a good rifle, no doubt

Alexander Florstedt