EMaxim, In the box labeled "Exakter Text im Stempelgerät oder exakte Teile davon" I typed "k 2 k" (with the spaces and without the quote marks). I get 6 cancellation devices. You just need to go through them and match up. Sometimes you get >500 devices; then you have to narrow the search. For example, the postmark on your stamp is a KBS (select in the box labeled [Stempelsorten (grobe Einteilung)] and in this case the number of hits drops to 3. [Stempel Typenübersicht] will show you images of the various styles of devices.
Some basic knowledge of German is required. Otherwise, Google Translate is useful. Regardless, some experimentation is necessary until you figure it out.
Thanks again. Can't wait to try it out. My German is actually pretty good. It's the technical terms that sometimes throw me. But they're becoming familiar now that I've switched from Scott to Michel for Germany and German area. Appreciate the help. Eric