67' Fastback Rear Glass Channel Rust Repair

I recently bought a 67' Fastback and the only real bad rust on the car is the rear glass window channel on the passenger side lower corner where the glass sets. Has anyone repaired this area before? It doesn't seem like a quarter panel will have this material on it so I'm assuming you'd have to custom make metal patches to kind of rebuild it? Anyone have pictures of their repair?

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