I found this website by accident today. It shows some old QSL cards from EI stations during the 1930's to 1950's. Certainly, working conditions must have been very different back then with most of the equipment home made or ex WW2 military gear in the 50's.
The QSL above is the card from the original EI7M station. It was re-issued some years back to the East Cork Radio Club who now use it in contests.