No one makes the repair panel that I know of. You will likely have to fabricate a repair.
Look for an underlying cause. Your hinges may be stuck or binding. With the door off make sure the hinges work freely. Remove the pins and inspect. Once the hinges are good then acquire a 36" length of 9/32" O-1 tool steel rod (drill rod, Mcmaster-Carr). You will use the rod as a common hinge pin for fitting purposes. Re-attach the door to the cab. Then remove the hinge pins and the door (leaving the hinge ******** the cab). Drop the drill rod through both hinges both on the cab and on the door, it should be a slip fit. If not the hinges are bent so the upper and lower hinge are not on a common axis which creates binding (and can damage the door).
Remember it is normal to have to bend the hinges some to align the door to the opening of the cab. It just needs to be done so the hinges are not binding.
If a hinge strap is worn beyond repair I do make replacements in investment cast steel.