Here you go, save some money on the other jets and build your own. https://www.sonexaircraft.com/jsx-2t/ Of course not quite the same performance envelope, and the hitch you build it, but a jet and a price tag under $200,000, even factoring in real costs as opposed to what they quote for the build. I'll probably pass, but I have considered building one of their other planes.
FYI you know that wasn't an option in this thread. Once you have an island, how are you planning on going there. City bus? lol Most likely you'll need a seaplane or a boat. kind of lonely being on an island by yourself.