I don't think this is from Falle. The tool is known as a Sputnik and everybody knows that the Russians built that one.
But seriously, as far as I know it was developed in Yugoslavia. A friend of mine owns one and is quite good with it, he even offers courses. I've seen him open an Abus C83 doorlock with it in ~30 seconds, which is probably half the time I'd have needed if it wasn't a very easy one.
He's from one of our german sportgroups and another member made hs own after seeing his. Basically you'll need a blank, thin steel wire, maybe a good drill press and you'll need to construct a good handle.
If you're a good craftsman it's a nice project.