Hi Scallywaggles,
I tried to find Mary McNamara, with a marriage to HARRIS.
Only one came up in the correct time frame, and also a daughter, born to the couple named Catherine HARRIS, in 1857.
Name:Mary Ann Macnamara
Spouse Name: Antonio Harris
Marriage Date: 1856
Marriage Place: New South Wales
Registration Place: Sydney, New South Wales
Registration Year: 1856
Registration Number: 281
1721/1857 V18571721 142A HARRIS CATHERINE ANTONIA MARY
Maybe, two deaths to this couple???
325/1861 HARRIS ROSEANNA ANTONY MARY A SYDNEY
1068/1868 HARRIS ELIZABETH ANTONY MARY SYDNEY
Death of Antonio HARRIS, in December 1872:
6126/1873 HARRIS ANTONIO AGE 58 YEARS DIED PARRAMATTA PARRAMATTA
On the Asylum record for Mary Ann HARRIS, it stated that her late husband was a seaman. There are a lot of entries for Antonio HARRIS, arriving in Australia, as a seaman, on Ancestry.
Maybe, he just used the name of John, rather than Antonio.
Most of his seaman entries, show that he was from the Indies; (Origin: Cape De Vew , Origin: West Indies, Origin: Cape and Verde).
From NSW State Records, Index to Unassisted Arrivals:
HARRIS Antema? 39 Acacia C 30 Aug 1855 Batavia 402 Cook & Steward, Cape de Verde; Java in SMH
HARRIS Antoine 33 Acacia C 09 Dec 1854 Melbourne 400 Or Stairis, Cook & Stewd, British
HARRIS Antoine 32 Acacia C 14 Mar 1854 Geelong 399 Cook, Portugese
HARRIS Antoine 33 Acacia C 28 Mar 1855 Melbourne 401 Cook & Steward, Cape de Verds
HARRIS Anton 28 Acacia C 09 Jan 1854 Geelong 399 Cook, Portugese
HARRIS Antonio 29 Acacia C 03 Jul 1854 Geelong 400 Cook, British
HARRIS Antonio 29 Margeret C 27 Oct 1855 Geelong 402 Cook, Cape De Verde; Arr date fr SMH
Mary