One point worth considering is this...taken from my observations: The HWKs most encountered with falsch markings appear to be those with the "long pin". Though believed to be of later WW2 vintage, my take is either this same pattern was re-utilized from wartime left-overs and/or made after WW2, as one of those supplied in the earlier W. German Rg34s. Because these tools were available in Europe until recently, they became fodder for fakery. I recall seeing them on Ebay and know there is a thread on this forum where these HKWs were discussed, pictured and the markings exposed as bogus (Found/see post# 13). I agree with CanadianAR that to make these HKWs new would not be cost-effective. The "adf" is not of the pattern of those tools.
One more observation: The bogus marked tools were done so with a die stamp "after the fact". This resulted in a sharp (to the touch) imprint with the metal raised around the letters/numbers. Though markings can be either stamped or "impressed" into the metal when formed, in doing so, the result is typically a "soft" appearance with clear markings and no displaced, raised metal ridges around the characters. Markings applied to components like the RGK swivel boss, because of the limited area available and round shape, are a different issue to deal with.