Robzy: I don't know about other states, but in NSW fictitious imitation firearms like Han Solo's blaster require a permit and safe storage compliance like Megatron. While Solo's blaster is based off a real gun, other fictitious guns which aren't but look realistic enough are also restricted. An example of this is Deckard's gun from Blade Runner; this is also prohibited in NSW despite not being directly modelled off any real life gun. But it's overall shape and colour make it look realistic to a lay person who knows nothing about guns, even with the two triggers (because if a person is pointing a gun at you in a dark alley way, you're not likely to stop and count the triggers; you're more likely to perceive it as an actual threat).
When applying for the permit you have a provide a description of your safe storage and I included a detailed description of this display cube. Considering that the NSW Police Ministry approved my application and granted me my permit, I'm assuming that they found it acceptable. I know of other people who use similar display units who've also had their permits approved too (in NSW).