Purgatory for those who are saved outside the Church?

The Catholic Church teaches that some might be saved outside the Catholic Church. This question relates to those, for example a non-denominational Christian that lives his life ignorantly but faithfully to what he believes is the Truth. Such a person dies, without the Graces of the Sacraments, but by God's grace alone is seen to be one of his children and graced with eternal Salvation. According to Catholicism, would that soul be responsible to pay the punishments for sin, which where not expiated during this life?