Very cool occupation time weapon! I suppose these are very rare?
These revolvers are few and far between, particularly when accompanied by a S&W factory letter. This is the so-called first style wartime "Victory Model" revolver that was made with a commercial blue finish and commercial wooden grips. Later versions had a parkerized military finish and had plain wooden grips among other changes.
The US Military issued the Austrian Police these .38 S&W caliber revolvers so USFA Occupation Forces could keep better track of the handguns and ammunition that were allotted to the reconstituted Austrian Police. The Austrian Police were not thrilled with them since they had been armed with semi-auto pistols for many years.
Here is another scarce Austrian made item... the proper holster. This black flap holster was made in the Austrian manner with two riveted belt loops and an ammunition pouch under the holster flap. This style of pouch for extra ammunition is a long time feature of Austrian Police holsters. The German style of holster is very similar to this but normally does not have the extra ammunition pouch.