Bankers' Special Boston Police question

I have a question for an expert on the Boston Police issued revolvers from the 1930 to 1939 timeframe. I always understood that the Boston Police numbered the Bankers' Specials with their property number on the backstrap starting with number 4000 and going to 4199 as the highest number known at this time. Gary Peer covers this in his great book on the Colt snub nosed revolvers, chapter 4. That would place the total number from this time period at 200 guns. I have never seen a BPD Bankers' Special with a low property number in the 2000's, but one is for sale with a BPD number of 2176. I believe this gun is a re-barreled Police Positive and not a true Bankers' Special, due to this low property number. The serial number of the gun is in the correct time frame (S/N: 355056) but without the Colt Archive letter it is impossible to say for certain that it is a Bankers' Special and not a Police Positive with a short pre-war Bankers' Special barrel installed. Can someone tell me what property number range the Boston Police used for the Police Positives? Thanks!

Mark K