I asked the same question a while ago, but unfortunately I’m still looking for one. I think if you are in he US you should be able to find one and get it shipped to you, but I’m in New Zealand and no one wants to post or ship here
You can fit a William’s to the 48/52, but you’ll have to inlet the side of the stock to make space for it. Get a M3 grub screw to seat the rear of the sight against on the receiver.
I would rather go for something like the Air Force TS1 sight or an old used Anschutz 6805.
The Williams is good, but it’s a lot of fiddling to change the zero.