I apologize if this is old news, but I was just made aware that Library and Archives Canada finished digitized their “ZK” prefixed photos. Taken between WWII and the mid-1960s, the collection includes over 3,600 colour images of the Canadian Army. More information on the collection is available here and a finding aid is also online.
There’s a lot of images to go through but I did manage to find, among others, some relevant to my research.
One of a series of photos of two members of the Veterans’ Guard of Canada posing for photos. The Veterans’ Guard was primarily composed of WWI Veterans who acted as a “Home Defence” force and guarded PoW camps across the country.

One of a series of photos of German soldiers captured during the Normandy Invasion. Quite possible that some, if not most, of these men ended up in Canada for a couple years. You can find the story of one of these PoWs, Richard Beranek, who ended up in a lumber camp in Manitoba here.