I had these photos saved of a No53 set up in PH rings and indeed as you say Nigel, there is a windage provision in one ring. Whether the other ring pivoted or just "did the twist again" as per many continental claw mounts I can't tell! :D
Probably NOT a military assemblage, given that the No53 can't have appeared before late 1943 or early 1944 from its once piece ocular lens cell.
Have seen photos of the Winchester .22s with No42 or 53 scopes on them, but don't seem to have saved any.
Previous discussion here: https://www.milsurps.com/showthread.php?t=65366
Much more detailed info here: https://www.rifleman.org.uk/Winchest...er_rifles.html
Though the purported SOE manual is indeed good for a :lol: !
The Winchester shown with an A5 or B4 scope fitted at the bottom of that section might suggest that the logical step of ordering the scopes as well as the rifles may in fact have been carried out? Though by WWII Winchester had long since sold their scope designs to Lyman.
Somewhat tangential, but there is a reference in Clive Law's Without Warning to "General Currie" [G.O.C. Canadian Corps] requesting the issue of silenced .22 automatics for snipers. Given the apocryphal references to "whispering death" in regard to the use of silencers by snipers in France in WWI, one wonders if in fact some such rifles were used there, and were the origin of these tales?