I should add that I've looked at the passenger list for the David McIvor and Maria gave her place of birth as Lymington but it looks like Leamington. Lyndhurst where she was born is only a short distance from Lymington. There is a document in the record office, Southampton with some family details relating to James which states he and Pricilla married in Lyndhurst just months after his father, William died(1757-1820, buried december of that year)and had 2 children there. Mary and Maria.
I have some more info on Acklands including Maria's siblings, Marriages etc as my direct line is James's brother William through to my maternal gran Lilian Marjorie b. 1903