Definitely mostly 70s, and they look in great condition. Very nice score!
I think that "Whalers" pennant might be the most unusual. Most Whalers stuff would include "New England" or "Hartford" but this one is blank. I'm not totally up on hockey teams, but that might be rare because it may be a pennant the team put out inbetween whatever time it didn't know where it would be! Just from further googling, might be from 73/74 if my guess is right.
Well, at least that's the piece I'd be most interested in (if I had any money at all to make an offer, I don't lol). Second is the Nuggets, that's pretty cool. Very nice buy.
I tried to find out what that pennant manufacturer is, since all of them include a team color bar on the left, so the same manufacturer (or I may be wrong and that's just the design method no matter the manufacturer), and so maybe if you email them you can get more accurate dates per each if that company still existed and someone in it was excited to go over archives and help you, but I failed to find it.
Great score and yeah, I suggest even more research because some of these might be very rare and valuable (by folks coveting such things).