Don't think that big metal head would've ever been used, except maybe for a spear...too top heavy to fly...where'd the other ones come from, they all look like obsidian.
JMO I don't think the metal point is NA it is a casted piece of metal. I can't tell a lot because I can't zoom in on your photos, the reason I don't think it is NA it has never been used ,no cutting edge and the base is to thick to haft to anything and use it. The way it is made it would have to go into a socketed shaft, and has I said before it looks to be casted and no cutting edge. I don't know of NA doing any casting and I may be wrong on that, if I am I would love to read up on it, because I have cast bronze points and other items. The Obsidian points are cool