You are (edited at @MOehm's suggestion)
I am part of South America politically
Geographically, the Caribbean islands are generally grouped as a part or subregion of North America, but politically, Providencia is part of Columbia
I am older than that
Providencia started as a colony in 1629, the Bahamas in 1718.
I unscramble the suffering caused by an ending marriage
"divorce pain"can be found anagrammed in Providencia
I unscramble a heavenly sound system by grotesque creatures
"Divine Orc PA" found anagrammed in Providencia.
I [don't quite] unscramble an adult clip recoded by an intelligence agency yields
CIA prn video
found anagrammed in Providencia.