There appears to be an original 16mm copy preserved
Australia's National Film and Sound Archive appears to have a clean original 16mm copy of the film in their vaults according to their website. This at the very least improves the chances that a future remastered DVD release is possible using that. I am sure there must be other similar copies floating around but the odds of them being properly stored are slim and therefore they will likely deteriorate with time. Link the archive listing is below
http://colsearch.nfsa.afc.gov.au/nfsa/search/display/display.w3p;adv=yes;group=;groupequals=;holdingType=;page=0;parentid=;query=Number%3A8211;querytype=;rec=0;resCount=10