Bill,
I frankly don't know.
I really don't understand the white metal buttons myself... but there they are. They look original to the tunic and are the proper "krinkle" style of pebbling by Assmann. That is to say, they are not the standard military issue style of pebbled button if you know what I am trying to say. All I can think of to do is to go back to the color of the swords and that would correspond nicely to these buttons.
I don't know about the pips either. The 1942 regulations state "Rosetten." Two Rosetten for Oberwachtmeister boards in either Justizwachtmeisterdienst or Werkdienst bei den Vollzugsantalten. This is the rank of both these tunics. The green Justiz shoulderboards are distinctive with the separation between the tresse but I don't know the dates for these. Perhaps Jiri knows?
Both of these collar tabs are green but I have seen the black ones too. Combine that with the black band on the peaked cap. Shoulderboards and collar tabs all have gold cellon trim, which seems to be rather standard.
Unfortunately, the only set of regulations we have are the 1942 regs that Gary came up with. These regulations show the tunic as having six exposed buttons on the front of a closed collar tunic. These tunics all (except for Bernd's eight button examples and Gary's open collar) have concealed buttons. I think these are earlier but that does not mean that they could not have continued in wear for some length of time.
It is confusing...
