We carry Survival/Immersion Suits with our abondon ship
gear. They are surprisingly affordable, as they are made for
commercial fishermen. They are immersion rated dry suits with heavy
insulation, built in floatation, built in strobe lights and fixed lights, and built in pick up harness for helicopter extraction. If I ended up in the raft I would be wearing one of these the whole time to prevent hypothermia if at all possible, in most situations. Even if long term sun exposure was a problem you could probably use the suit to get around it somehow with the
hood up and the zippers open.