In fact it is an officer model 1871, because this model did not change until the officer model 1915. (the higher point, and the Reichskokarde on the right have no effect on the model)
The infantry troop model, alone, is called the 1895 model (ventilation of the rear bead, fixing of the frontal plate by bridges, etc.)
Regarding the monogram, you should look at the reverse but I have the impression that it is a B in stamped and stapled metal, and not an embroidery.
Officer's helmets were still bought commercially, and in times of peace the German aristocracy and nobility practiced the profession of officer by tradition.