Hi from across the ditch.
I would suggest the ultimate response to the machinations of your government bodies is to grab something like a traditional Navaja, 19-22cm in length. They obviously can't be opened with one hand, with the carraca they can't even open them by shaking them out, but unlike the Delicas or Ladybugs that are one handed opening, they are a weapon designed to substitute for a short sword. The carraca was the last thing heard by many a man in the dark streets of a Spanish town. There are Spanish websites around that stock them. Also don't forget the Cold Steel Eland. Although they've been discontinued they're a very large two handed opening folding knife that is mercifully cheap. I have three.