not clear originally. those thend to have the chrome fading after decades. they were clear plastic with chrome inside.
available as reproduction from all vintage Ford parts suppliers. sometimes NOS or NORS show up on ebay. Take care to get the right ones ( 2 different designs). Non back up lights cars have solid, wide trimrings and back up light cars ( mostly Fairlanes and special order on cheaper models) they have many cutouts to the side ( allowing for the brake lights to brighten up the outer part of the lens. I think the Fairlane trim will go over the Custom (all red) taillight, but not the other way around.