I have a collection of 492 ear trumpets - a Guinness World Record.
These ecologically sound devices are rarely used anymore.
The range of shapes and materials used in manufacture is astounding.
I collect any related item that is a good discussion point when showing the collection. Thus I have a couple of monaural stethoscopes and some other items which were possibly used as ear trumpets.
Also there are some items which are not actually ear trumpets at all but demonstrate some of the things passed off as such.
I would be very interested in hearing from anyone wishing to sell a genuine ear trumpet.