"Stock" is harder to define with bikes esp. those imported during the 1970s "boom." Numerous bikes in threads in this forum are original but don't match their catalogue. Add to that the fact that many top-enders came as a frameset which would be specced by the buyer and built by the shop and that customers frequently swapped components on bikes before they left the floor. You can check the stock list on your '68 Camaro for originality but it's not as easy for your DeRosa.

"Period correct" seems to be the common goal and as mentioned above fairly easy to achieve. The big thing would be to keep your gruppos intact, no Dura Ace mixed in with the Campy . (Though to be honest I put together a 531 frame originally specced with N. Record and the front derailleur was irreedemably ugly and I used a very clean DA changer and the Gods haven't struck me down......yet.