Tinpis, I will have to go through some old photo albums, but I am pretty sure that their was a PA-31 around Melbourne in the late 1970's with the callsign VH-UFO, it used to transit through both Essendon and Moorabbin on a regular basis. It may have been owned and operated by Bizjets.
Ummmmm.....I have walked around this aircraft when it was parked up against the GA fence in Canberra circa 1972.
Help me here....somebody musta been alive in Canberra at that time?
It had
VH-UFO painted on it
It looked like **** personally
Whether the registration was taken up or not I have no idea
Try Google VH UFO P51