The online subscription websites would be my last port of call when seeking South Australian passenger lists. The survival rate for ships' manifests in SA is not good.
Di Cummings, now deceased, compiled and transcribed passenger lists from various sources including newspapers of the day, and if additional information was available from other resources, it was added ie possible name of wife if passengers were listed as Mr John SMITH and wife and/or four chn. Possibly sources from birth registrations in SA. Researchers of SA history are grateful Di lodged her research with SLSA. Her CD mentioned is no longer available. I do have the one for early arrivals but at the moment, can't find it. I rarely use it these days.
You are seeking records of passengers, many of which paid their own fares and those lists were often compiled from the passenger lists published in The Register.
State Records of SA hold the following for
Inward Passenger Lists
Series
GRG 56/68/5 -
Index to passengers arriving at South Australia from overseas ports 1836 -1845
GRG 41/8 - Manifest of incoming ships at Port Adelaide 1838 - 1842
SA Records have digitised passenger lists from
1844.
This website also has passenger information for early arrivals and details ALL the sources of information used to compile same.
http://www.familyhistorysa.org//shipping/passengerlists.htmlI wonder if there is anything of interest to you in this publication
The Rajasthan : the ship, her passengers and voyages to South Australia 1838 & 1839-40 / Helen Scarborough
Scarborough, Helen (Helen M.)
https://catalogue.nla.gov.au/Record/2244779/Copyright?Cheers
Cando