I have seen a couple go for almost three grand but around $1,500-1,800 is more realistic.
It could be chambered for the Rigby but the chamber walls would be on the thin side. Rifles dedicated to the Rigby usually use the Magnum action with a larger diameter. Although it is a long action it is the same as the standard M70 with the bolt stop moved back and a larger magazine and ejection port cut. But check with a gun smith as I am not one nor a metallurgist.
The 404 Jeffrey would be a good fit.
"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli