Country folk involved in operatic number (7)
I believe the answer is:
armenia
'country' is the definition.
(I've seen this before)
'folk involved in operatic number' is the wordplay.
'folk' becomes 'men' (I've seen this in other clues).
'involved in' indicates putting letters inside.
'operatic number' becomes 'aria' (I've seen this before).
'men' inserted within 'aria' is 'ARMENIA'.
(Other definitions for armenia that I've seen before include "Republic formerly in the USSR" , "Transcaucasian nation" , "Landlocked country, an Asian soviet before 1991, capital Yerevan" , "Landlocked country south of Georgia" , "Former Russian republic, its capital Yerevan" .)