Sue, yes, much of this information appears to match with what I have. If James Starkey & Margaret Lewin married in 1863, then a son, James Joseph was born in 1864 which is the right age for the grandson James Starkey living with Lewin grandparents at the time of the 1871 census. My William Starkey was born 1867 which also fits with that same census. With the 1881 census with William listing occupation as Farm Labourer also fits, this was his occupation on his NZ marriage cert in 1900 and he went on to own his own farm.
*Note I have found a misprint with the name, Slarkey instead of Starkey in some searches.
Janette