Hello jellywerker,
Welcome to the site.

When you say low teen, do you talk F or C, in other words, do you talk cool or freezing. That does make a big difference.

The coleman site blanket gives in their descripsion that you need a few for camping. The army surplus site is not as generus with information, but my own experience with ex army blankets, (European) and like woolen blankets, is that they are a nice extra, but not survival gear.

If you go camping in below freezing temps look for a good sleepingbag or at least a modern blanket designed for that kind of temps.
I do not know what a glightish jacket is, I asume it covers you warmly on the upper body, but remember that you legs are going to loose a lot of heat if not properly covered.
Also look into bedding, either natural or modern, small and lightweight, that can save you in freezing temps or make a misserable night into a nightmare if done wrong.

Success with the experiment and enjoy the trip.

Willeke

I'm interested in a blanket as opposed to a sleeping bag for two reasons . One is cost and the other is weight and ease of rolling it up tight . What are your plans for a shelter ? I've camped out for many years using only a sheet of plastic and using dry branches and twine for a "tent" . I use the space blankets only for my super lightweight pack for one nighters only . I'm interested in your final choice . See the thread survival backpack and the sling . I assume you'll have a sling . Another gentleman on this site carried a bow and arrow kit in his pack which I admired . He said he carried broadheads and a string and fabricated the rest out in the woods . I'm going to assemble a "kit" like his .

Wool is supposed to be warm even if wet . That would settle my choice quick .

Wool has long been the choise for outdoor activities in temperate climates. But it has been outclased by manmade fibres in recent years. Most minus freezing sleepingbags nowadays pack smaller than a woolen blanket and are as waterresistant.
In cold climates wool was always used next to fur, because that is much more windproof, and that in itself keeps you better warm.
A (modern) fleece layer with a wind and waterproof outer layer are warmer than wool ever can produce.

If you go for authentic, and above freezing, go for wool.
If you go for below freezing add or replace by modern stuff.
For sleeping a mummy style sleepingbag with the hoodpart closed is the best, I should say only option if you want to pack compact. But fit the sleepingbag in a shop, it should be snug but not tight (when you are at your full growt).

Willeke

If you can find them, nothing beats a couple of Hudson's Bay wool blankets. They have kept fur trappers and explorers warm for 400 years. I would go with older ones ( 1900). They are thicker and more durable. I use two for Klondike camping, and am toasty.
  Whitney blankets are also good, but not quite as warm.  James Townsend and son sells them. They are worth the investment, especially if you plan on doing this for a long time.
  Aslo, remeber to have a good hat on . You lose 90 percent of your heat out of your head.

Thanks , now I'll add a hat to my pack

A sling only weighs at most a couple of ounces 

I do not keep up with the new developements, so better go to a site where they compare sleepingbags.

The brands are likely different in the usa anyhow.

Using one of those sites will give you comments of users too.

And remember that your reflexes like feeling cold do not work when too cold and that can be deadly.

Willeke

This is one of the sites I wanted to show you.
http://comparestoreprices.co.uk/compare-prices/sleepingbags
click on the sleepingbag name and see the user reports.

Do not trust them if you see no negative reports too.

If you want more sites, google on 'compare sleeping bags' (without ' )

Willeke