You also have to stipulate no welfare or other assistance.
THere has to be some form of income. It won't be shops, or arts and crafts, since no one from outside will come in. I think the existing level of welfare and foodstamps would have to be maintained. I don't know what you do for external jobs outside the sealed experiment. And I don't know what jobs you can have internally that are government or free market. Firemen will be assaulted. No one would work at a CVS. It will be a food desert. It would take some thought as to how to set it up, and it would likely be impossible to get agreement on it, anyway.