For some pics of old ostomy appliances have a look at
www.ostomates.org/vintage/index.html A friend of mine took these at an ostomy meeting he went to and let me put them up on my site.
They're a lot older than 20 - 30 years though. 20 - 30 years ago we had plastic appliances but not quite as flexible as they are today. I used to use a stomahesive wafer 30 years ago too. It was more like 40 - 50 years ago where the rubber appliances were in use. Imagine having to wear some of the stuff pictured!