Hi Myles, At this time, there are no reproduction sill plates available for 300F or 300G. This project has been suggested to our Reproduction Parts committee . Therefore, the best current source for decent sill plates is salvage yards . The good news is that ANY 2 door, hardtop or convertible, Chrysler 1960 through 1964, all models, uses the same sill plates ! If yours are rotted out, then the easiest / cheapest/ best way out is to locate a good set of used ones, probably from a dry area such as Arizona, etc... Yes, 1960 thru 1964 NewYorker, Windsor, Newport, and 300 models will all interchange and are exactly the same. As far as restoring a good set of used sill plates to their original finish, they must be stripped of their anodizing, buffed out, and then re-anodized. Sincerely John