This was advertised in our area recently as a class 5. Much larger than that and looks space age so I had no choice but to buy it. At a guess about 3 m wide, square timber stub axles that fit into an aluminium frame fibre glassed into the body. Wheels are 4 ply wide wheelbarrow 16.5 - 8. Front steering casting has broken where it enters the chassis. mast is approx 100mm round section with 3 guys, it has a ball end that sits in a curved hole on the body. A weathered sticker on the front shows Newcastle Boat Mart and a round sticker on the rear seems to show a galleon style of ship. I'm guessing from the East Coast in the 1980's.
Thanks for the confirmation Gizmo. I found the old post on this model and my one appears to be a third known orange one. It spent 15 years in a shed near Narromine prior to to me getting it recently. It came from the east coast before then according to previous owner.