Re: A few questions before I can answer
No, each is wearing leisure wear appropriate to their time whether that is jeans/khakis what have you, vice animal skins/furs.
Each start off with no weapons, but can fashion weapons based on what they can find in their environment. (So, while it's possible the astronauts know about things like guns, bow and arrows that the cavemen may not, that doesn't mean they know how to actually make one, and the cavemen will have spears clubs, atl-atls, etc. that they know how to make).
I will say we are talking homo saipien cavemen, not neanderthal so, no more hairy than the average human. (but clearly, you appear to be into that...not judging!).