(after starting with just "Whymark NSW" and adding words to cut down on the hits) I got 45 hits. You might repeat the exercise. Most of the genealogy on the net is for people born before 1900, to protect the privacy of the living and recently departed. If you have your grandfather's birth, death and marriage dates, plus his wife's maiden name, it helps.
You will probably have to find Hector's parents through his death certificate or obituary to get back to pre-1900.