Don't discount the accuracy or killing power of the 7x65R. I have a 6x42 Zeiss on mine and I have shot Roe deer out to 200 metres with this set up.

On the assumption that the two sets of mounts and bases are identical - ie you can use either mount on either set of barrels. Are these quick detachable mounts? I think the standard valmet mount is onto a dovetail which should be fast to remove and replace with acceptable return to zero.

I would be getting a pretty standard 3-9x36 or 4-12 x42 scope which will give you all the magnification you need to for longer shots - mainly for use on the 222 barrel, and for the 7x65R ideal would be a 1.5-6x42, or if you were doing a lot of driven hunting a 1.25-4x24.

Leupold do a 1-4x20 Scope - the Hog scopes - are 1" tubed and really nice and small and compact, and 4x is more than enough for anything bigger than a head shot on a rabbit at 100m. And wind it back to 1x perfect for giving that fast running fox a charge of shot. But to be honest I have shot enough foxes with the shot barrel of my combination gun with a fixed 6x42.

If I am shooting flying game, scope is off and rifle barrel is empty. If something rifle shootable appears, use the open sights, or slip on the scope.