Join the Dark Side
It was years ago that I first saw the Imperial Star Destroyer LEGO set in a store and coveted it ever so much. It was out of my budget at the time, and still is now that it’s discontinued and collectible. More than that, I don’t know where I’d put it. The thing is huge. Luckily Ryan has all the fictional space in the world to build his Imperial Fleet.
Still, it’s likely that he used the more toy-like model, which is still pretty expensive, if not quite as massive. And of course he needed the Super Star Destroyer Executor to be completely accurate, and properly awesome.
There would be no getting around using Death Star II though, which is also discontinued and priced exorbitantly. The other Death Star option is more like a play-set, and doesn’t exactly look like a Death Star.
The whole thing would cost a small fortune (feel free to do the math), but funds aren’t the only reason to cut the Rebels out of the battle. They don’t actually make sets of the bigger rebel ships, like the Medical Frigates and the Mon Calamari cruisers used in the battle. The closest to it is the Home One set, which is the interior and hangar of the Mon Calamari cruiser where the battle briefing took place. Not really appropriate for space conflict.
It is just as well. The dagger like shapes of Star Destroyers (and the name) make them much cooler anyway.