dried egg / egg powder?

[iworemyfringelikerogermcguinns]

I'm going to try some recipes from an old wartime cookbook but a quite a few have dried egg or egg powder in the ingredients (eg a dessertspoon of...)

Would anyone know either where I can get dried egg (other than scrape off dad's tie lol or from sports supplements shops where they may contain other ingredients too), or what the measures might equate to in "real egg" terms

all egg puns are welcome.

I am not sure of the eggsact quantities but I would try a heaped tablespoon of dried egg powder to be about 1 egg.