If it's primarily the armrests that are a concern, they are repopped - both the chrome base and the small foam pad on top. If they're the ones I'm thinking of, they were used pretty much universally in 65, on P, D, C - across the board . . .
Just downloaded the '65 Chrysler sales brochure from the www.eatondetroitspring.com website. Fill out the menu for vehicle model and such, then go to the upper horizontal menu with "Links" at the far right when the page with the spring numbers and such appears. That gets you the sales brochure (for ANY model of vehicle they build springs for). IF it might matter, the brochures are for USA-spec vehicles, as some Canadian vehicles are different in some areas.
The '65 Chrysler door panels and such were unique to 1965 only. With NY having a completely different panel from other model trims. Non-NY models have a separate pad on top, which should be replaceable and might cross with other C-body Plymouths and Dodges.
Most of the repros are for the '66 and later model years. There are two lengths of them, so measurements are needed. Bases and pads.
Sorry, my bad. Went back to check the 1965 catalog. Sure enough, NY door panels are different from the 1965 300, Newport, and all the other Plymouth and Dodge C-bodies that I can think of.