While searching through my old issues of Dragon yesterday in a quest to locate something for Mike Monaco, I cam across an ad from a company called Kabal Gaming Systems. The company was selling "Dungeon Floor Modules," like those picture above -- sheets of paper/light cardboard on which were printed rooms, corridors, staircases, etc. to be cut out and used in conjunction with miniatures.
I never owned these or indeed saw them, but I did have a similar product from Heritage USA, called "Dungeon Floors," if I recall. They came in a small box (like most Heritage products) and were made of rather sturdy cardboard. Unfortunately, I only ever owned one set, so, even when I did use them, I had a limited range of shapes and sizes for my dungeon layouts. They certainly don't hold a candle to the Hirst Arts blocks we use nowadays.