I use Eastwood 2k epoxy primer and Eastwood 2k 'universal' gloss red for steel wrenches and 2k rally wheel silver for aluminum handles. It isn't like modern Ridgid Red which is much more orange than red, but is pretty close to the older ~ 1940's Ridgid Red, which is the majority of what I do resto work on.
For the hook jaw and adjustment nut, I would suggest just removing the rust, letting them soak in oil for a bit and calling them good. You can cold blue the heel jaw, heel jaw pin and spring clip, which is how I have seen most of the NOS & replacements from the factory.
I do like powder coating, but with the cost of powder coating seeming to ever increase, its not really something I opt for on hand tool and most small power tool restorations anymore. Eastwood's 2k epoxy automotive paint provides a pretty durable and oil resistant finish. Its also nice because its available as a 2 component both in rattle can and for HVLP application.