Cut oranges into thin slices. Stir together sugar, bourbon, water, and fresh lemon juice in a deep, 10-inch skillet. Cook over medium heat, whisking occasionally, 3 to 5 minutes or just until sugar dissolves. Add orange slices in a single layer, and simmer 10 minutes. Turn slices over, and simmer 5 more minutes or until tender. Remove orange slices, 1 at a time, shaking off excess syrup. Transfer to a wire rack, and let dry completely (about 4 hours).