and you are not an expert on vintage pieces,my advice is, tread very very carefully. HK is a horological paradise but doesn't really have the culture for vintage.Authenticity is a major problem and if you are going back to the 50s & 60s,verification and provenance can be problematic. Authentication papers can now be easily altered and replicated.
If it's your first Rolex, why not buy new? It may save you a lot of money and problems in the long run. I understand the allure of vintage Rolex but unless you are or have the help of an expert and a 100% trustworthy seller, the pitfalls far outweigh the advantages IMO.
cheers
fernando