Well this was a surprise to find!
Paul was absolutely correct I still have no firm clue as to the origin of the body. The floor pan was clearly moulded off a Triumph Herald as it has all of the floor pan ribs and indentations, including holes etc. The sills however are far too high and are similar to an E-Type jag as it the door curvature, door length and height in relation to the sill. The roof and rear quarter panels have been cut down to narrow them and alter their shape - which we found out when we stripped some paint. The front clip clearly came out of a mould - but it does not match any known kit/car/special I have been able to find. It is quite possibly a one-off, whoever did it had quite a lot of skill.
Not much has happened to it since the images were taken - my 16 year old son has taken a liking to it and what father can dismiss a son's interest in old cars!
Due to Australian road rules, were I to construct a chassis and use the Alfa running gear I have stored I would need to register the car as an individually constructed vehicle and I would need to meet emissions standards. This has made me follow the path of returning the car to what it was - mostly. I have agreed to purchase a rusty Triumph Herald that had a Nissan A14 engine and gearbox installed in it in the early 1980's. I can make the argument that in keeping all of the original running gear, scuttle and chassis I am simply changing the body shape. It will still need engineer approval, but this route means the car will run again. Someone, somewhere put a lot of work into this and I feel that the car should be saved.