I have a set of 4 Pyrex restaurant dishes in the Grecian pattern that was available from 1959 to the end of the Pyrex Opal dishes in 1986. The are marked with the Décor logo, which dates it from 1959 to 1963.
These bread and butter plates are #704 and are 6-3/4" across. They are in excellent condition with little wear and no chips or cracks. We use these dishes from this line in our kitchen as they are very sturdy and look great, both in the cabinet and on our dinner table!