They're not "stationery" in my mind - one doesn't write messages on
them or enclose messages in them, or send them as though they were an
envelope, letter sheet or postal card. At most, they are stamps. I
define stamps as "prepaid receipts for postal services". IRCs are
"prepaid" and they are used for "postal services". The German term
"verrechnungsmarken" ("settlement stamps"] seems to fit - because
those were generally stamps that one did not affix to a piece of mail,
rather an official pasted them in a record book and cancelled them as
a record of a completed payment or funds transfer.
Regards
LN
Post by Lars EngelbrechtDo you consider International Reply Coupons (IRC) a Postal Stationery?
Best regards
Lars Engelbrecht, Denmark