Yeah, you can modify the magwell if you know what you are doing or send it out and get modded to take AK mags. Its not a big mod.

Thing is, if cops/military are grabbing guns in a time of disaster they won't care if its a Saiga or a full blown AK. They were taking .22s off of old women in Katrina. Get something small, folding stock, SBR, whatever, and be low key, you won't last very long with any weapon otherwise.

Surefire does make hi-cap Saiga mags, they are more expensive and much harder to find that regular AK mags but if you don't want to go the mod route you still have hi cap options.