http://www.rebelgunworks.net/products/oscar-model-57-12-gauge-15376
Mate, if you want some thing to look at & discuss, could you please have a look at the Oskar 57 at the address above.
I have tried to work it out by research on the net & I even rang the shop. The phone call was unproductive to the point of frustration because of no further information.
I have never heard of the breed before. Oskar as the first name of the maker but not Oskar by itself.
One day I may go & look in person if it is still there when I next go to Brisbane. Possibly I might need it because it looks a bit on the heavy load capable side.
O.M.