Hi Chloe,
Archives NZ Wellington only have an Index card for the 1863 voyage, with the following sources given;
[i]Otago Gazette [/i] 1871 p.183
(arr. Bluff 27 Sept 1863 dep. 3 July 1863)
This might be the source for the on-line passenger list mentioned above.
"SP 2/2" (SP = 'Southland Province').
This material is on microfiche #7104-7121. I checked it but found it to be indexed correspondance from various parties. I ran out of time to check section 2/2 but it appears likely to be similar material possibly from former a passenger/s of the Helenslee voyage who might be applying for a job in government, or government correspondance relating to the voyage.
Regards, riley.