Sign for the note in foreign currency (5)
I believe the answer is:
libra
'sign' is the definition.
(sign of the zodiac)
'note in foreign currency' is the wordplay.
'note' becomes 'b' (musical note).
'in' is an insertion indicator.
'foreign currency' becomes 'lira' (I've seen this in another clue).
'b' placed into 'lira' is 'LIBRA'.
'for the' is the link.
(Other definitions for libra that I've seen before include "Zodiacal sign" , "stars" , "Someone born between September 23 and October 22" , "Constellation near Virgo" , "Old pound" .)