Using a fork, in large bowl combine flour, sugar, orange peel, baking powder, and baking soda. With pastry blender, cut in margarine until mixture resembles coarse crumbs. Add cranberries and currants; stir to combine. Add buttermilk and vanilla to flour mixture and stir to combine (mixture will be dry). Form dough into 2 equal balls. Preheat oven to 400 F. Sprinkle clean work surface with 1 tablespoon reserved flour. On floured surface, using fingertips, work one-half of dough into 6-inch circle, about 1/2-inch thick. Cut circle into 6 equal wedges; place wedges on nonstick baking sheet, leaving a space of about 1 inch between each. Repeat procedure, using remaining flour and dough. Bake until lightly browned, about 10 to 15 minutes. Remove scones to wire rack and let cool.