Custom-made by Ken's Rings, this Super Polaris Mount adapter attaches to the top of your SP mount allowing you to use a scope with a dovetail rail/bar.
Maximum width of dovetail bars that can be used with this saddle plate are 1.75" (45mm) at bottom and 43mm at top. Make sure your dovetail bar is not wider than this (this is a custom-sized one).
Paid $100 new for it less than two months ago. Sold scope that used this. Will let this go for $60 ppd in U.S.