Hi again Colin,
This is on this site also;
http://www.familyhistorysa.info/colonists.htmUREN James Sweet, Elizabeth Ann CUNDY married 1849-09-08 at Trinity, Ade, aged 25, 17
UREN James Sweet, Elizabeth Ann CUNDY, parents of child born 1850-05-13 named Elizabeth Jane at (TMu)
UREN James Sweet, Elizabeth Ann CUNDY, parents of child born 1851-06-22 named Elizabeth Jane at (TMu
UREN John, Mary Ann SWEET, Jas Sweet, John, William arrived 1847-07-02 on Trafalgar (1) from London via Plymouth 47-03-18
So looks like Parents John/Mary Ann nee Sweet and Son John 1824 who then married Elizabeth Ann Cundy
Now I was looking for your Richards possible Baptism and found this Marriage on FreeREG;
Richard UREN to Alice SWEET, 16 June 1794, King Charles the Martyr, Falmouth
Now Familysearch.Org has these Children Christened Falmouth to RICHARD/ALICE Uren;
RICHARD, 3 May 1795
ALICE SWEET Uren, 3 March 1797
EDWARD Uren, 14 May 1800
GEORGE Uren, 5 June 1805
LOUISA Uren, 13 July 1815
FreeREG has;
Richard 1795/Alice Sweet 1797/Edward 1800/Elizabeth 1803/George 1805/John 1811****/William 1812/
Louisa 1815/Joseph 1819 (birth 1817)/Charlotte 1819
Marriage on FreeREG Bodmin, John UREN/Mary Ann SWEET, 12 July 1824
Not your Richard but another Family from Cornwall that ended up in Sth Australia