Webb's believes Mr Bouma's was the largest single vendor collection of timepieces to have been sold in New Zealand.
The auctioneers will offer a remaining 300 pieces from the collection on November 7.
Mr Bouma, who died last Christmas, aged 91, assembled it over a 60-year period lasting well into a retirement in which he doubled up visits to overseas relatives with excursions to antique shops, flea markets and swap meetings at almost every opportunity.
Born in the Netherlands in 1923, he lived through World War II under German occupation, when a fascination for electronics began after he and his father built and hid a radio set so they could listen to news reports.
He was said to have a thirst for knowledge of how things worked - from clocks, nautical instruments and radios, to gramophones and cameras - and was a civil and electrical engineer before serving as the oil refinery's general manager for several years in the 1970s.