Thank you for your suggestions. I have the convict records for these transportees from the Mitchell Library and some information from the National Archives of Ireland and reckon I've gone as far as I can among the Public Records. Hugh Anderson is a correspondent and found me the details and then a neighbour working in Sydney had them copied for me.
What I need is a way of tracing people beyond the convict records. What further archives are there? How useful might newspaper inquiry be - which would be the best newspapers to approach with a letter - or even with a feature article?