Here's my 52, bought a year or two back from a dealer- described as an
"Original" [and yes, it is in inverted commas]
CLASSIC Mod 52 in .22 and dated (I think - it's tiny) 05 91.
I haven't found references to one quite like it online. There's no provision for open sights, a barrel sleeve, and a muzzle weight, evidently some sort of UK special - but with a conventional (and rather nice) Walnut stock.
The butt pad isn't contemporary with the piece - it originally had a ventilated "Wiking" pad which was falling to bits. I never thought that finding a replacement could be such a task, or I'd have tried to knock something off the price.... in the end I got a gunsmith to size something down to fit.
https://imgur.com/cpY36PA
https://imgur.com/oneZ4t6
https://imgur.com/gvdvn4M
https://imgur.com/YhWjMO3