I have a M77 22WMR in a Zytel paddle stock. This was bought on a strict budget and it came with rings, mod but no sight. My spare sigh didn't fit as the bolt caught the back of the scope.

So I looked at higher Ruger rings and they were between £40 and 60 so I discounted those as I eventually wanted to mount a nightvision unit on it so had to buy the Brittania rail adaptor - £100.
The standard mounting system looks to be really sturdy and eventually will go for a variation for .308 so I can use it on Boar and Deer and will look for a used M77 in .308 I think.