Yeah, obviously I have a thing for these guys, the H-34 as well. It seems like the options are endless as so many people used them for so many different things.
The silver is just silver paint, as far as I can tell these were always painted not left natural metal because they used a lot of magnesium and magnesium corrodes very easily. Somewhere I read that these had a higher % of magnesium in their construction than any aircraft before them.
If you get going on the Revell USCG kit, two things to watch for are the seams along the fuselage / tailboom and getting the orange in just the right spot. The black stripes give you a little wiggle room but not much. Also the winch in the kit is wrong for the USCG versions, they used a winch more like the one in the UH-34 kits. Technically neither of my USCG helos are finished because I haven't got around to building a correct winch for them (and just realized I forgot to put the winch on the UH-19A).
The winch in the kit used an internal motor with a folding boom that could be swung to the side when not in use.