Tom, I think you're a little confused mate, you studying too hard! lol Raw Hide is hard as old boots and certainly not ideal for making pouches...I'm presuming you meant Buck Skin lol
Bumblebee's right, they looked like Swedish coffee bags, no doubt picked up the idea from Lars
I'm sure one of our first nation members will correct me if I'm wrong but I was under the impression that while medicine bags were not exclusively so, they were mainly on the small side (compared with coffee/flour bags) and used to carry special herbs and charms etc. I seem to remember Oh Canada mentioning them not too long ago.
For the pouches you want Halo, I'd say 2mm would be fine. You can get scrap leather off evilbay pretty cheap, just do a search for scrap leather or similar and you'll find it. Failing that, nip down to your local charity shop, pick up an old 80's style Micheal Jackson leather jacket and cut that up to make your pouches, that way you get to mak mistakes without worrying about costs and you also give a little to a good cause.
Hope that helps matey,
Bam.