Chas; yes, the seller sent me the picture of the rear of the wappen.
Brian; I agree with you about the lack of bandeau. What I am not sure about is whether this state used the normal "FR" wappen and just superimposed their state plate on top or whether they used a wappen without the "FR". "Stubbs" seems to suggest that at least one Bn of the Regiment used a normal Prussian line infantry wappen....so I am confused.
I think this was discussed on the old forum but for the life of me can't remember the conclusion, although I recall their was at least one strong theory that the independent states would never have used the "FR" wappen out of sheer pride of their independent status.