I have seen a Weaver type mount system that fits into the removable block in the rib of a Krieghoff double rifle. It enables you to use a scope or red dot sight easily. Does anyone know who makes these bases?

Krieghoff makes a pivot mount that I know of.I believe the rib needs to be dovetailed for the front mount and the back uses the section at the rear of the rib.I got to sight in a scoped Krieghoff .500 N.E. for a friend.Not something you will do twice for a friend.

My Krieghoff barrels have 2 claw mounts and one pivot mount. The claw mounts have rings and the pivot mount uses a railed scope.
I have never heard of the Weaver mount.

I was wrong, here it is. It's carried by "Eurogun Imports" it's in Guns America for $250.00

Weaver type base

That reflex site/ double rifle combo is probably the ugliest firearm I have ever seen.

Looks like a weaver blank base that has been machined off and drilled to fit the removable block. I used parts of a ruger rib and machined to fit the removable sections of my Chapius rib. Machined parts to fit flush with top of rib and drilled to use the Chapius mounting holes so it could be returned to original with no trouble. Had to use medium height ruger rings as the low rings did not give enough room to operate the lever comfortably. Very nice looking and functional. The Chapius was a 9.3x74R.