I'd try to stay as close to the original colors as possible
Ray
Back in the 1970's and '80's, when we were dealing (on a very small scale) in govt. surplus equipment, we had some of those come up in various lots.
Most were 'original', which meant that they were painted with thin coat of a sem-gloss black., presumably the cheapest paint which would keep the iron from rusting.
Some had a bit of gummy paint inexpertly daubed on the lower hook frame.....in 'safety yellow'.
I've a vague memory of different sizes of those chain falls, as new commercial stock, hanging on the walls of supply houses......best I could remember, they were just plain black, with the chains 'bright'.
cheers
Carla