Analogue Automatic Watch (1970s )

I can't give a fair range for the R49,999 asking price. This is a 1970s Zenith automatic with date in an 18ct case, about 35mm, sold by a dealer with a 1-year in-house warranty. Without a reference number, there are no matched sales or priced listings to compare it with. International dealers do list similar 34mm 18ct Zenith automatics from the 1970s, but I couldn't confirm their prices. Treat the asking price as untested, not as overpriced or cheap.

What could change this: The exact reference and calibre (for example a hi-beat or semi-hi-beat calibre such as the 2572), plus whether the case is solid 18ct gold and the dial is original. Some 1970s Zenith dress watches are gold-filled or gold-plated, and they sell for much less than solid 18ct.

Missing evidence: I need confirmed sale prices, or at least dated asking prices, for 1970s Zenith 18ct automatic-date watches of the same reference or calibre. Local sources would be best (for example Royal Watch, Chrono24 South Africa, auction houses such as Strauss & Co or Stephan Welz). International sources with prices and dates would also work, such as UK vintage gold-watch dealers or auction records. I also need the subject's reference number, calibre and photos of the hallmarks.