26 1/2" x 1/2" black metal strip - door frame

[Czechmix]

Just inside the angled portion of the left and right doors is this black metal strip that runs the straight length of the angled part of the door frame. I honestly never paid attention to them, except that my body shop removed one of them to do some work and no longer has it. I'm speculating that they serve to create a better seal against the weather stripping, but I'm not certain. Does anyone know what these are called and where I can find a replacement for my RH door? Attached pic attempts to show this strip on my driver's door.