De Rosa didn't sell complete bikes - he sold frames. Whatever components are hanging on that frame, somebody else put 'em there. It could have been the importer, it could have been the shop you bought it from.
Alos, at that point, De Rosa did nto really have "models." Based on the age, I believe (but am not positive) yours would be called a "Professional," but there wasn't a choice between a "Professional" and a "Primato" and a "Classico," at least not then. You'd get a De Rosa - period. A model name was, at best, an afterthought.
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