Preheat oven to 350 degrees F (175 degrees C). Heat oats on a baking sheet in preheated oven for 12 minutes. Set aside to cool.
To Make Crust: In a medium bowl combine oats and 1/4 cup brown sugar together; mix in 1/3 cup butter. Press firmly onto bottom and sides of a 8 inch pie pan. Chill for 1 hour.
To Make Filling: Combine 3/4 cup brown sugar, flour, salt and milk in a medium saucepan. Cook over medium heat until thick, stirring constantly. Remove from heat and stir in 3 tablespoons butter and vanilla. Transfer mixture to a medium bowl; cover with foil and refrigerate for 1 hour or until cold.
Once cold, fold in 1/2 cup of the whipped cream. Pour mixture into pie shell; chill until set. When ready to serve, top with dollops of 1/4 cup of whipped cream and arrange 6 pecan halves decoratively on top of pie.