Scope for a long action custon Mauser

! have a problem. I have a custom built rifle circa 1966. It is based on a long action BRNO Mauser action. It has split ring Redfield mounts. I need to replace the optics. The problem I am having is that the outside to outside measurement of the rings is over 5.6 inches. It appears that modern hunting scopes are shorter than in years past and most current hunting scopes have seem to have a maximum 5.75 mounting length which does not allow me to adjust for eye relief. the period scope that was on there was 14 inches long. Am I relegated to putting a vintage scope on this rifle-which I prefer not to do? Nor do I want to put a tactical scope on it. The only modern brand I have found with a 6 to 6.25 length mounting tube is a company called Alpen which I know nothing about. Any other suggestions will be appreciated.

The Burris Signature Select line has apparently been discontinued, but there are still some around. A couple of those models had long tubes.
Leupold has a long 3X20.
The (also discontinued but not all gone) Nitrex 3-10X50 has over 6" of mounting length.
Burris, Leupold, and Nitrex are all excellent scopes.

Looks like an opportunity for an OPMOD model long-action scope.