Nishiki did have some Nishiki branded, but "third-party" [including Italian] built frames, the Ultimate, the Maxima, and the Cervino. I have no idea if the line-up included track frames, though, but I wouldn't consider it out of the question. I also don't know if this work resembles any of those 3 models.
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72 Frejus (for sale), Holdsworth Record (for sale), special CNC & Gitane Interclub / 74 Italvega NR (for sale) / c80 French / 82 Raleigh Intl MkII f&f (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 09 Giant TCX0 / 10 Vassago Fisticuff