The One Million years B.C./She double bill, is excellent, but there was a lot of extra ones printed. As they were a give away to the public. You just wrote to hammer, and they would send you one, FREE. ( Ar, the good o'l days )
So it's supply and demand, and always will be. it's the only way anything is worth what it is.
Do you have a problem with Text on posters Mel, as I quite like text on them. I even have some posters that are all Typographical, and I love them. If you want posters with no Text, maybe you should buy old Pace, or Athena posters... As unfortunately film posters have to say what the film is, and who is in them, etc etc.