A friend of mine went through this some time ago. I *believe* that this is the situation - but I do not claim to have any official or expert knowledge.
You need to submit copies of:
1. licence
2. medical
3. logbook
All three need to be certified as true copies and submitted to CASA.
The Australian legal requirement is that these documents need to be cited by an individual with the same requirements to certify a Statutory Declaration:
http://www.ag.gov.au/statdec has links to details.
You can try a DAME, Notary or an Embassy official - or anyone on the list. Some are easier to find outside of Australia.
Also, dont forget the security requirements and the associated forms ....