Hi John,
I'm not sure whether you have found the shipping records yet but here they are from
www.records.nsw.gov.au/archives/indexes_online_3357.asp#ImmigrationampShippi Assisted immigrants arriving in Sydney & Newcastle, 1844-59.
Surname Firstname Age Remarks Vessel Year Reel WILKES Charles 31 and family Kate 1854 2137, 2466
WILKES Edwin 1
WILKES Mary 35
WILKES Samuel 9
WILKES William 5
PIGGIN Eleanor 33
The records may show age, occupation, place of birth, parents names, religion, whether they could read/write, if they had relatives in the 'Colony' and the fare.
I have been meaning to check a few other immigration records so I could check this too if you like. It may take me a week or two.
Believe it or not, I also have an interest in this family (although a very distant limb in my tree). Rose Wilkes (born 1886, G/daug of Charles) married Thomas Cheeseman in 1908. Thomas was a nephew of my GG G/mother.
Would you happen to have found the Charles & Mary in the 1851 Census? Are you in Aust ? Happy to swap info.
Libby