Shenango Inca Chardon Rose Platter

This platter measures approximately 11 x 8 inches. It is backstamped with green Shenango Inca Ware and a Design Pat. The Design Pat. backstamp, may help pinpoint the actual manufacture date, as not all the Inca Ware pieces have this particular addition. There are no chips, cracks, breaks or rough rim and the pattern design has no loss. There are superficial usage and cleaning marks to the surface. The color is not showing the tan of the plate. I need your zip code to calculate the postage.