Russell, unfortunately the Compass II uses a specific 5rd Rotary Magazine : midwestgunworks.com/page/mgwi/prod/tc-compass-mag

No its designed to be a hunting rifle, and many states have restrictions for the capacity a hunting rifle can have, 5 is on the higher end of most dedicated hunting rifles, not to mention that a large magazine on a hunting rifle would stick down and could affect your ability to make shots from a prone position, you may want to pick up an AR, AK, mini14 or some other modern sporting rifle if you need something with a much larger capacity.

NO, there are NO larger capacity mag options for Compass II. They only have 5 rd mag.