Lightly spoon flour into a dry measuring cup; level with a knife. Place flour and sugar in a medium saucepan; gradually whisk in milk. Cook over medium heat until thick and bubbly, stirring constantly. Place eggs in a bowl; gradually whisk half of milk mixture into eggs. Pour egg mixture into saucepan; stir well. Cook 1 minute or until thick. Remove from heat; stir in 1/2 cup coconut and vanilla. Cover surface of coconut mixture with plastic wrap; chill.
Spoon 1 1/2 tablespoons wafer crumbs into each of 6 (8-ounce) glasses; top each with about 3 tablespoons coconut mixture and 2 tablespoons whipped cream. Repeat layers once, ending with whipped cream. Sprinkle parfaits evenly with remaining coconut.