I recall seeing scores of old log books in the late 70's in Vic. Most had just 1 or 2 flights. But rarely did they have lots of hours.
There were a couple with low hours but in the front, you would see an old log book referred to that might have been Spitfires or Lancasters. Back then it was not uncommon for a fit looking middle aged guy to walk in, want to get back into flying and you would discover that their last flight was in WW2.
Perhaps the books could be kept in storage and the names placed on their web site.
I cannot imagine CASA assisting as they would claim it was an invasion of privacy.
The other alternative is for high quality scans to be made of the log books before their disposal in
the very rare probability that someone older than 60 is going to show up looking for an old logbook.