Tengu, moccasins are broken down into 2 major categories, plains and woodland and to a degree this dictates what materials you would use.
Woodland moccasins have soles which are made from the same material as the upper, whereas plains moccasins invariably have soles made from rawhide (nowadays it would be veg tanned leather).
Eric mentioned brain tanned buckskins, well to a degree that is correct, the Native Americans or First People, however you wish to refer to them, had a choice of materials to make things from. Moose, Bison, deer and Elk amongst the choices.
Deer is the main one for moccs IIRC, but you are not limited to that, I have brain tanned Moose hide moccs that I made, it was expensive to buy, very expensive to import, the service from the supplier was exceptionally poor and to add insult to injury when it finally arrived (I waited for a year) I had to pay customs and excise. For about 8 feet it cost $150 to buy, another $125 to import and then customs hit me for £40 odd quid. So before anything else it cost about £170.
Nowadays the equivalent to brain tanned is chrome tanned leather, no it's not traditional, but it opens many more avenues to explore and is cheaper (unless you find a friendly tanner in the UK to do you brain tanned deer or along those lines).
If you are making them yourself I would suggest getting in touch with
Yatahai as they have a good number of designs and styles of pattern, I have seen patterns in other places that look the same (that's because they are), Yatahai is run by Sparrowhawk and Sparrowhawk publishing are who make a lot of the patterns.
It may be worth getting in touch with James Watson, he is a member of the forum and does a bit of brain tanning, so there is a chance that you may be able to get decent brain tanned stuff here. If he cannot help you then hit ebay and have a dig about for chrome tanned or drop me a PM and I'll let you know who I use on there.
As for the hats, I cannot really tell you a lot about them, I would have thought either Oil tanned or Oiled veg tan of around 1.5mm thickness.
I hope this is of help,
Leon currently sat in one of three pairs of moccasins that he has.