I'm hoping some day to make a 1920's type case for my krink like they made for Tommy guns. Until money/time frees up though I'm using a simple softshell mandolin case. Has a pocket for paperwork, and can fit with the stock extended, a magazine in it, and a 4-mag pouch. (I dont keep it loaded when carrying it obviously, i keep the empty mag in it to keep the shape of the case/be able to carry 5 mags)
I live in a fairly rough part of the city, and most cops are (rightfully so I guess) really on edge. My new range is in walking distance, so I try to keep it as discreet as possible for now so I don't get questioned. Cops here hate guns, I can't imagine what they would think of this one!