Food, fuel etc.
Fedex does not deal in postage stamps.
You'd buy four with 44cents left over.
For postage stamps you go to the post office. For rubber stamps a stationary dealer should be able to help you. Then of coarse there are also the the type that are used for compresing loose soil...
the best place from where you can buy stamps is the post offie
In World War 2 petrol, paper and clothing were also rationed in many countries.