Oh, how things have changed.
Consulting my 1937 copy of The New Ettiquette by Margery Wilson, I learned that one never refers to the paper used in letter writing as “stationery”. The correct terms are “letter-paper, note-paper or writing-paper.”
Nowadays folks would just be happy to be on the receiving end – regardless of what it’s called.
(I apologize for the fuzzy quality of these scans. The book is 75 years old, fragile and slightly warped. It becomes a little clearer when clicked on and enlarged. When I find my camera, I’ll try photographing the pages and see if that improves the appearance.)