Hi Airmuster,
This is the aircraft that used to be at wangaratta in the museum. It was a messenger similar to the mercury but with a fixed undercarriage and two rudders instead of three. I believe it is under restoration here in Victoria. I am certain there was no mercury in Drage Airworld.
here is a picture of your fathers mercury VH BBK
this is a good link detailing the history of all the messengers/mercury's that made it to Australia
MILES MESSENGER IN AUSTRALIA
it says here that on 7/8/56
the registration of VH BBK was Changed to VH KCH
then on 30/10/56
the ownership changed to W. Gall, "Langawirra" Station Broken Hill NSW
then 20/11/58
It was Struck-off Register as "reduced to spares"
So it could still be hiding in a shed somewhere!!!
Hi Kolby! another one for the miles club here! interesting machine the mercury!