There's a place here in Az that uses old bathtubs as forms and vacuum forms plastic sheet into liners and then installs the shell inside your tub. Never seen it, just heard of it. Rebath (usual disclaimer)
Otherwise, lots of sanding, wiping and white epoxy paint, as used on boats. Ship-n-Deck.(usual disclaimer)
If you live in Brooklyn, NY, you could find a place on Atlantic Ave. that would re-enamel that clawfoof tub with the real thing. Go a couple'a blocks and there is a guy that will sell you original tin ceilings, and another guy around the corner that has vintage paints and colors (lead free of course). Keep looking and there are imported tiles (all the rage at the time).
I did a lot of restoration down there. Blew me away what is available if you have the cash.
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Send a PM to CR4's 'Kris'. What Kris doesn't know about baths isn't worth knowing.
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