Douglas,
Not exactly what you were asking, but here is what I have on my Ruger No.1 .450/.400 Jeffery:
https://www.ebay.com/itm/353887096978?hash=item5265509092:g:rv0AAOSwTN5h-azz

I'm a Leupold guy and like the M8 fixed power scopes, they do pop up on occasion.

- Mike