Thanks, Mark & Rich!
Rich - the people who have told me about the commercial prints have all commented on the inferior quality of the printing. I have to say, this one looks quite well produced. Does one of your two sizes correspond exactly with this one ... dimensions and print credit ... ?
Mark - your description of the paper quality tallies with this one - and I would agree - if it had been a piece of commercial merchandise, there surely would have been more around - or at least, more people remembering them.
So far, I'm tending towards the idea that it is some form of original theatrical item - Mark's suggestion of premiere or larger cinemas seems very reasonable.
Thanks again.
Terry