It's actually a Morat SMG, same one as on the krakot more-or-less (at least going by the dossier). I know it's part of the head thing, but now I've made the association all I can see is a dick dastardly moustache in play:
Personally, I plan to paint her forehead as some sort of mask. Or the bottom, I'm still not sure... It depends of me prefering a visor-halfmask or a breather-halfmask