The first number in the serial number is probably the year. If you look to the right of where it says Chromage Super Chromix you might see a 2 digit date code in a diamond. The Chromix rims on mine had this stamped on them.

Your bike is in super condition. The one I have came with clamp on shifters and a bump on the downtube to keep the clamp from sliding. Yours has braze ons. Interesting.