Without some sort of heat source, I couldn't imagine how you'd keep those wattles warm! Will he drink from a nipple waterer? I'd worry about him dipping those into his water bowl. If he's housed alone, you might have success with some sort of head wrap

Insulating the coop might help. Is that the setup he's in, with the open bottom? Can you sneak him somewhere warm until you've got a game plan? When I've got an urgent coop upgrade I need completed I sneak chickens in dog crates into my husband's garage next to his precious tool box and wham! Solutions are found fast!