Peel, section, and seed enough oranges to make 5 cups of orange sections; drain, reserving 3/4 cup juice. Set aside about 1 cup of orange sections for topping.
Combine sugar, butter, orange juice, cornstarch, water, lemon juice, and orange rind in a medium saucepan. Cook over low heat, stirring constantly, until slightly thickened and bubbly. Remove from heat; stir in 4 cups orange sections.
Place 1 pastry round on each serving dish; cover each with 1/3 cup orange sauce. Top with remaining pastry rounds. Spoon remaining orange sauce over each. Garnish with a dollop of whipped cream and an orange section.