I need this symbol since I use it a lot in correspondence.
Weirdly enough AltGr+4 produces the Euro Symbol (€) on my keyboard.
It seems that these are the ways to get the symbol:
AltGr+e – Works in most European countries
AltGr+u – Hungarian and Polish
AltGr+4 – UK and Ireland
AltGr+5 – US International, Greek Latin
Try it and see which one works for you.
Also, AltGr can produce some of the European accented characters (é,ú,í,ó,á).
I think this only works in Windows.