I was also a bit doubtful as this looks nothing like what is usually described as the "old tower" at today's SYD and is very similar to Parafield as Dave suggested.Perhaps there was an even older old tower at SYD? Anyway, here's the first of the Qantas 749s arriving at Sydney in Oct 1947.
Sad to read that G-ALAN ended its days on an Alaskan mountain side in 1960. Looks beautiful in the OP's photo.
