Thanks for the comments. Here is a back view of that holster. I agree that the date is more likely 1944. If it is a post-war fake, someone went to a lot of trouble with the pattern and even the button. I have simply never seen one like this. The pistol itself would have been appropriate for WWI. As 1944 issue under the pressures of late WWII bombing, etc., it makes some sense that it might have a substitute standard holster. Could have been a "Home Guard" sidearm or a Police gun?

CamoHolster by jakefromclemson, on Flickr