Kurt Glemser, a moderator on GDC in the European edged weapons section, wrote a chapter in his volume 2 that gives a great history and makes note of the variations between Eickhorn and WKC.
The South African daggers(of which this is an original) were authorized in 1965. I do not see a serial number on your dagger. The Eickhorns are serial numbered.
These are very impressive dagger and, of course, are from the last racist government we acknowledge.
Nice dagger.
Jim
