Hi John,
I recall there is a Cerberus preservation trust in Oz that does something like a card model and/or drawings of her. As she was built for the Australians, the NMM, might have drawings. It is possible that the builder or their archive holders might have something of use. As for the wooden steamers, then lots of Googling will turn something up I am sure.
Do a search on this forum as well, as there are at least eleven years of topics that may hold something?