Here are the pictures of the WDR 23 knife in the OP...
Notice the similarity of this WDR 23 knife to the one I posted above, WDR 4.... same model same etched initials and Randall stamp, same handle and spacers, same escutcheon plate, same engraving on escutcheon plate. One could reasonably speculate that there was a special limited edition produced in 1962-63 with brown button Johnson sheath, display box, etc.... all identified with "WDR" initials and a number. It would be interesting to know what this was all about...