I've got two vintage cars I've been restoring for a long time and have had plenty of rust to deal with.
I would suggest removing the hinges, sanding off loose paint & rust, cleaning them and then using a rust converter paint like Rustoleum. Rustoleum is an excellent product and sticks like sn@t over rust and looks good if the surface is prepped correctly .
The key is correct cleaning of the surface before application of the paint. Do not use POR-15.
Personally I don't think it's worth spending the time and effort to strip the hinges completely to bare metal.
Rustoleum is also good for under an RV to deal with rust on the frame and various components.