No prop firms. Might be a regulatory problem or maybe just no demand. Have you looked at IB? That would be the only English platform that I know of. I looked around for one for someone else but no luck. With so little demand for one here in Japan that's understandable. Also, IB would be the best for leverage with the exception of Himawari. They offer 50% of SPAN for Nikkei futures and are considering doing so for Topix futures too. IB is 50% of SPAN +25% As you already had an account with Matsui, I figured you didn't have a problem with Kanji.