In a small bowl, combine the salt, with sage, thyme, peppercorns and paprika. Pat the turkey dry. Set in a large roasting pan and rub it inside and out with the spice mixture.
Preheat oven to 450 degrees. Stuff the turkey body cavity and the skin flap with the chosen stuffing, packing it loosely. Brush the turkey with melted butter and roast for 30 minutes or until the skin is golden brown. Scatter the onions, celery and carrots around the turkey, add the water to the pan and cover the breast loosely with foil.
Lower the oven temperature to 325 degrees, and roast the turkey for about 3 hours longer, or until an instant-read thermometer inserted in the thickest part of the thigh registers 165 degrees. Remove the foil for the last 15 minutes of roasting.
Transfer the turkey to a carving board, cover with foil and allow to rest for 20 to 30 minutes. Pour the pan juices into a medium saucepan and skim the fat from the surface.
Set the roasting pan over a top burner, stirring well until vegetables are brown. Add 4 tablespoons of butter and the flour, stirring well until well mixed. Stir in the turkey or chicken stock and whisk until gravy boils and thickens. Simmer gravy for 15 minutes. Strain the gravy into the pan juices in the saucepan. Discard vegetables. Season gravy with salt and pepper. Carve the turkey, arrange on a platter and serve with the stuffing and gravy.