Could be a sluggish thyroid/subclinical hypothyroidism. My advice would be to try supporting/nourishing your thyroid with supplemental selenium and iodine (just make sure to slowly increase the latter to avoid triggering any reactive hyperthyroidism). Consider upping your carbohydrate intake to at least 20% if not there already, and make sure to balance your muscle meat intake with gelatine, as excessive tryptophan and cysteine can have antimetabolic eg anti-thyroid effects.

I have poor circulation due to a disability; I set hot water bottles on my thighs when I'm sitting at my work desk. They really help to keep my entire body warm. Using cayenne pepper caps as a supplement can also help to warm you up & to improve circulation. For some reason, I also tend to feel warm when I'm fasting -- it's weird, because I know that most people get chilly when fasting; not sure how to explain why I often feel a warm, buzzing feeling when I'm IFing.

Ever since I got my D level up on the high end (91 ng/ml), I have noticed no more cold extremities.
In fact, I seem to be running warmer lately.

I used to have Reynaud's as well, but not since going Primal.

I'm a Minnesotan who sets my thermostat down to 62 in winter, and I learned something priceless years ago, pre-paleo, but relevant. DO NOT wear long-johns in the house. Or I mean, don't try to keep you legs warm by other means. Regular trousers are fine of course, or bathrobe or whatever, but go chicken-legged underneath.

Your body needs to feel the chill in you extremities in order to regulate your core temperature appropriately. Sacrifice your legs to the god of winter, and you'll always have springtime in your heart.

Ooooo, that's gotta be the worst turn of phrase I ever came up with.

I have Raynauds, have had for years - white numb fingers and toes if they get cold. Only 2 years ago I found I had thyroid disease - hashimotos. As Simibee said there is a common link.

I found auto-immune paleo with more than 100 grams carbs a day, fish oil, magnesium, regular food and fluid (dehydration triggers attacks) all help.

I always get cold extremeties in the cooler seasons - it kind of makes me not want to move - but therein lies the solution - I usually make myself just get up and move around (even just a few star jumps and a quick high intensity wriggle around!). Gets the blood flowing and makes me warmer.

I am hypothyroid and used to ofen get cold hands and feet. One thing that helped was to wear magnetic insoles in my shoes- seems the increased circulation helped.

Now I just deke out and go to a warm country in the winter.

Check into a traditional Chinese herbal formula called Si Ni San. It's good for the microcirculation and can help with cold hands and feet.

related paleo hacks question:

http://paleohacks.com/questions/25624/raynauds-disease-cold-numb-white-toes-and-fingers-and-paleo#axzz1YgGaKZE9

Since you asked for techniques to keep your hands and feet warm in the winter, you could wear gloves when you're outside and a sweater when inside. Wear heavy wool socks all the time. Thermal underwear also works but can be uncomfortably hot.