This is only a partial answer.

In Saga of the Greenlanders (which features several travels to Vinland) there are some references to the native Americans' "leather boats":

"Þá fór innan eftir firðinum ótal húðkeipa, ok lögðu at þeim." - Grænlendinga saga, 5.

Roughly translated as: "Now came several leather boats from the fjord, sailing towards them."

Later there is also a scene where a native picks up an axe and, not knowing what it is, kills his companion with it:

"Nú hafði einn þeira Skrælinga tekit upp öxi eina ok leit á um stund ok reiddi at félaga sínum ok hjó til hans. Sá fell þegar dauðr." - Grænlendinga saga, 7.

Again, roughly: "Now one of the natives [not the word they use] had picked up an axe. He looked at it for a while, raised it towards a companion and hit him. The man fell and was dead."

In conclusion, I would think it plausible that the writers of 13th century Iceland had at least some concept of the technological stage in which the native Americans where at, about 150-200 years earlier, Which in my eyes at least is somewhat remarkable.

I hope that answered some of your questions.

I will do my best to answer your question, and at the same time keep to the rules regarding that it must add to the discussion.

I have read a book full of the Viking Sagas, but only a few are about Canada, then called Vinland because of the abundance of grapes.

They do sometimes discribe their contact with the natives, although this is mainly in terms of trade. Which gives us some interesting insight and some educated guesses as to what the natives had to offer, and therefor had and wore themselves.

Mainly the natives are interested in weapons and red cloth. On every instant of trade mentioned they want to trade their "fur pelts and sables and all kinds of skins" [1].

Further on in the saga a woman is mentioned "wearing a close-fitting tunic, with a shawl over her head and light red-brown hair."

Then, as described in the saga, there is a turmoil because a servant killed a native for trying to steal a weapon and they (the natives) leave behind their clothes and trade good, but nothing is told about te clothes.

Then. Regarding weapons there are parts where natives tried a steel axe they found after a battle on a tree and marvelled at how well it chops trees, but they decide its useless after it breaks when trying to chop stone [2].

Then something else interesting is described. Eirik the Red met a vast group of natives who swung poles counter clockwise (previously they swung them clockwise to signal peace and trade). This time they mean war: "they met and began fighting. A hard barrage rained down and the natives also had catapults. [...] saw the natives lift up on poles a large round object, about the size of a sheep's gut and black in colour, which came flying up on the land and made a threatening noise when it landed."

Apart from somebody being killed by a arrow, there is little description of their weapons.

I dont have any sources on when others made contact with the natives of that region, so this is as far as I can explain it for you.

Overal source: The Sagas of the Icelanders, published by Penguin Classics

Sagas: [1]: Sagas of the Greenlanders [2]: Eirik the Red's Saga

I'm not an expert on the Grænlendinga saga or Eiríks saga rauða, but they are publicly available so I did some digging.

In Grænlendinga saga chapter 4, Leifur and Þorvaldur find remains of a "cornhelm of tree"^1 . A cornhelm is a shelter used to crush corn^2 .
In the same chapter Þorvaldr is shot in the hand by an arrow, showing that the Skrælings had bows and arrows.
In chapter 6 Þorfinnur Karlsefni mentions that the natives wanted to buy their weapons, which were mostly made of iron and wood, offering furs, with grey squirrel and Sable being mentioned by name.

In chapter 11 of Eiríks saga rauða there is described a battle with the Skrælings, where they are said to have "valslöngur"^3 , or slingshots, and that "þeir færðu upp á stöngum Skrælingjarnir knött mikinn og blán að lit og fló upp á land yfir liðið og lét illilega við þar er niður kom"^3 , which means "The Skrælings moved a large blue ball up on poles and [the ball] flew up on the land over the group and behaved badly were it touched down"^3 . In the same chapter the Skrælings come across a steel axe, which they first use to chop down a tree, which works well, and then on a stone, which breaks the axe^3 .
In chapter 12 two Skræling boys are kidnapped and taught Norse. They describe that two kings rule over their lands, Avaldamon and Valdidida, and that their people live in holes and caves, but not houses. Opposite of their land is a land where the people wear white clothes^3 .

Sources: 1. https://www.snerpa.is/net/isl/graens.htm
2.http://timarit.is/view_page_init.jsp?pageId=4365962&issId=294909&lang=da
3.https://www.snerpa.is/net/isl/eirik.htm

Can anyone answer the second part, that's what I'm most interested in?