I know that Canadian units had M1911s and the Brits also had M1911 pistol "British Service Model" which used .455 Webley. (Also removed the glock tag and add the M1911 tag)
Possibly but remember, this is based of the game where you can choose whatever weapon you want. For example, that is a lever action rifle strapped to the Tommy's back instead of the Lee Enfield, the standard British Rifle at the time.
I heard that British officers bought the Mauser C96 very frequently though. Until the war happened and then didn't want anything to do with Germany anymore.