Rusted inner door brace

[Mike-fire32]

I am in the process of replacing all the window channel felt, wing window rubbers and belt line seals on my 70 F-100 Ranger. There is a brace located inside the door, below the wing window and just forward of the front window channel that is rusted and broken. It appears the brace is there to keep the door halves from separating. Has anyone else experienced this issue, and is there a reasonable fix for it? Without these braces, the door halves move apart, allowing water to get down past the wing window rubber.