The Miyata model 1000 was arguably the best grand touring bicycle by a high volume manufacturer. They are very designed and manufctured. Based on the serial number yours in an early 1980s version, around 1982. Tubing should be Miyata Cr-Mo double butted, which was actually manufactured by Miyata, specifically for their bicycles. Components around this period would typically be Dia-Compe cantilever brakes, SR triple crankset, SunTour Cyclone MKII GT derailleurs and Sunshine Gryo-Master hubs (40 spokes in the rear). The bicycle came standard with front and rear racks, About the only feature that it was missing, with respect to the best touring bicycles of the era, were bar end shifters. Some of the later models had more features, but for the time, this was one of the best you could buy, without going custom built.