That is literally the perfect "zombie apocalypse" gun! Whisper quiet with a suppressor fitted, accurate at 100m (head shot range), virtually no recoil, very rarely breaks, easy to clean and (in the US especially) plentiful ammo!
over here too, i'd wager the .22lr is the most common round to find here (excluding military stocks of .223 ofc)
when it comes to zombies everyones of the vein of "i'm gonna carry a .50 cal" despite the practical reality that the barret is a tonweight to carry, grossly impractical to fire from anything but bipod deployed prone and round energy is pointless if it's a headshots only scenario.
i'll admit i'd settle on one of the henry .22 leverguns if i couldn't find a 10/22 but they're a pita to reload in a hurry, but stealth is key and as you say whisper quiet.
would also allow you to hunt things like rabbits without turning your dinner into a pink smear on the landscape.
i feel vindicated that the us put a lot of research into the m6 survival rifle and ended up at the same conclusion that a .22 was the best (albeit a magnum so you could more easily kill deer or defend yourself)