Free: Contests & Raffles.
Puffy jacket, puffy pants, puffy mitts with hand warmers, fleece or merino wool neck gaiter. Make sure everything has a windstopping layer. Also a jetboil or similar for a hot drink helps a ton.
If you are over 55 have your iorn levels checked. Cold hands and feet are a symtom.Also, get in shape and eat high calorie foods while on the hunt.