You might be better to contact an Apple fanatic or Apple variety rescuer. They might narrow it down to type. I remember a recent story about such a person travelling around re locating lost varieties.
There are many varieties of Apples, we now know the fresh eating types, but many older types are for cellar storage or cider. Dont write off the flavour too quick. I have a few seedlings here, and truth be told they usually "dont fall far from the tree" fruit wise, although they seem to change a bit in later years.
There are a lot of wild roadside apples around Canberra and other similar areas in Australia. Mostly you can guess the parent variety.