To clarify what is available. There are two major Level D Boeing 737 full flight simulators (meaning they have six axis of motion) in the Melbourne area. While these are primarily for airline pilot type rating, command instrument rating tests and recurrent training, both are often used for flight experience trips. One is at the Qantas Flight Simulator complex in Matthews Avenue opposite Essendon Airport which is part of the suburb Airport West. The second is Ansett Aviation Training in Garden Drive, suburb of Tullamarine, off Mickleham Road.
There are other flight experience synthetic ground trainers around which are mock-ups of the 737 NG. These do not have motion. One is in Bourke Street in the CBD and another in Keilor Rd, Niddrie near the junction of Matthews Avenue and Keilor Rd. There may be others of similar design and situated at Moorabbin? Obviously the price for an hour flight experience varies, depending how realistic you want and on which devices you can afford.