The discs should be the same on early or later carbed SSssss.....all with the round holes in the rotors.........but ST3 snowflake discs will fit (because I have some on mine).... As should the rear wheel, although the colour would be different (ie, white as opposed to silver/grey)....... Front wheel is different from about '94, even though at first glance they look the same....It's all in the hub machining, y'know.... ......but a 600 or 750 wheel would fit as well, as long at it is the right 'era'.
I meant to say, the front wheels differ because of the speedo drive diameter........the easiest way to tell if it is early or later, is to look at the central brake disc 'retaining ring lug' on the speedo drive side........Early wheels; the lug is approx 6mm wide and later wheels it is approx 4mm wide...... Top pic = later (shows the thinner grease seal as well) Bottom pic = early (courtesy of Chewythekneeslider)