Never powder coat things which go outside,shotblast epoxy prime then 2 pack poly.The door lock is easy to source so I would consider having the door bead blasted and either repaint or have it powder coated
Never powder coat things which go outside,shotblast epoxy prime then 2 pack poly.
You keep saying this Trev but I disagree with you, powder coating is durable and easier to apply, alloy wheels, motorbike frames, towbars etc are powder coated, if it gets chipped which would allow rust to start you can treat it just the same as you would with paint, the only thing I would worry about is if the metal door is sturdy enough to stand the heat of powder coating but a quick visit to a recommended powder coating company would get the answer to thatNever powder coat things which go outside,shotblast epoxy prime then 2 pack poly.
Try Stedalls, they do all kinds of commercial body fittings, in their catalogue there is Fuel filter flap which looks like what you are after.