The .40 cal liners for Remington doubles that I have seen were for .40-70 "Sharps and Remington Straight." Easy to make if you have .30-40 empties or can be purchased formed as per previous poster.

Never saw one made for .40-65 Win. Doesn't mean there aren't any but I would bet they WEREN'T made by or for Remington--in those days they avoided the "W-word" at all costs.