Reads like a great build the high end Nishiki's from the 70's are just great frames there build guality matched nearly anything made in that time frame built up this bike should ride near perfect. I have owned one and road it till the frame wore out after 4 wheelsets a couple of crashes and about 10,000 miles. You should be able to find most all of the parts fairly easy. The 750 Diacompes that most of these had are even still in production.

http://www.amazon.com/Dia-Compe-Long...e++center+pull