Wiring is intact, the whole unit appears to be a very good original. The plastic (nylon) tends to yellow with age and exposure to heat/dirt/grease, perfectly good patina. Notice the color difference from Belair's valve to the one on your RS. It also matches the color of your washer pump nylon.
If you ever disassemble it, be extremely careful with the hose on the end fitting - the wall where it blends into the lower valve housing is extremely fragile - a very thin wall, brittle plastic, and will crack or break off if you are not aware of it. Belair will sell parts, or at least they quoted me in the past, to replace lower valve housings along with the needle/spring assembly inside (which usually falls out or lost when the hose bib breaks). I would leave this one just like it is, install the hoses and nozzles if they are missing, and enjoy it. I'll include a link to get the silver part tag on the next post.
Regards,
Steve