Ron,
Here in an image showing the serial number.
The individual numbers of serial numbers (and characters) are not allows stamped perfectly right and the B-suffix does not appear suspicious to me. The so called 'halo' on this pistol does not follow the characteristics of natural halos I have observed on other Lugers.
One detail which I am not 100% sure is whether the B-suffix was stamped after the serial number or below the serial number - I guess under the serial number. Maybe you can refresh my mind regarding this method. I know that the the presentation carbines in the 9100 serial range have the number stamped as 9102C along the forearm tang.
Albert
