n = 501 is not good enough for you? Seems decent enough. "In practice, pollsters need to balance the cost of a large sample against the reduction in sampling e

n = 501 is not good enough for you? Seems decent enough. "In practice, pollsters need to balance the cost of a large sample against the reduction in sampling error and a sample size of around 500–1,000 is a typical compromise for political polls." https://en.wikipedia.org/wiki/Opinion_poll https://en.wikipedia.org/wiki/Opinion_poll