I recently bought this pristine, stock Nishiki Competition on Ebay for $150. Assuming your components are in good shape, you should just find a similar frame and transfer the components. Definitely not worth repairing that frame!
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1971 Paramount P-13 Chrome
1973 Paramount P-15 Opaque Blue
1974 Raleigh Professional Blue Mink
1991 Waterford Paramount
Holland Titanium Dura Ace Group
Holland Titanium Ultegra Triple Group