Here are images of the two most "common" Recht en Trouw buckles and I am sure that a one piece stamped variation exists also. In my opinion, the one shown by Klinger is a fake and which is a type having been known for many years - without any stamped markings. It would appear that the fakes are now available with bogus and nonsensical marks.
These images have been "extracted" from a post that Marc Verstraete van der Weyer made on another forum. I will drop a line to Marc and if for whatever reason he objects to their use, I will delete them.
Klinger, have a good read of this thread, it may help you a little
This buckle was for the flemish DM/ZB (not dutch) brigades, why should there be a RZM mark as these were made in belgium?
Just to chime in on the markings, the buckle being for a Flemish organisation, it certainly did not come under RZM control, and for the same reason there should not be any "ges. gesch." marking either as this, again, is purely German. Plus, the "SS" obviously intended to sex this thing up...
Best regards, Kurt
Again, I do not know original die stamped specimen of these buckles.
Here is my "belgian made" zinc buckle for comparison.
Please try further this side (under topic belt buckles):