Unfortunately due to a server glitch, we have lost most of the old posts. There was a lot of scope info for the K-31.
What scope mount and rings do you plan on using?
A scope with a large bell well need fairly tall rings for the bell to clear the front sights. If you are going to use a clamp on mount it well offset the scope to the right. Add a large bell scope and this offset is kind of exaggerated. You end up with a chin weld and not a cheek weld.
For mil-surps I prefer a fixed power scope and really like the older Weaver steel tubes. They are low cost and have good glass. I big plus is they have a smaller bell than the newer style of scopes on the market.
This is a 4X Weaver K4 on a SP mount. You can see how close the bell is to the rear sight.
Here is the offset you well have.
I find a 4X is plenty of scope for out to 300 yds or so. I do want to hand a 6X condor on one of the K's for longer ranges.