I would estimate that this blue QA is from around 1990, give or take a couple of years. Looks like conventional size tubing and classic campy dropouts. Steel QA's from the early/mid 90s were built with the newer oversize thinwall tubesets from columbus and reynolds and also utilized more modern style dropouts. Later 90's QA's were aluminum and carbon.
Headtube decal indicates Italian manufacture which was probably good indication of decent quality construction. Once you get a better look at the oria decal you can hopefully get better indication of what tubeset it has, Oria specs at a minor: Oria Tubing Specs
Oria made some good tubesets. Last steel frame to win the TDF was a oria tube Pinarello (Indurain).