Consider use of IB account, NIY symbol root. In-case you mean futures "&" options, current SGX contract is NKM3 for futures, Yen denominated. Will be listed under SGX CME. Flat futures contract is ~$4000 USD margin, ~$25/tick, 5-point increment. Respective options, which I do not trade and can't comment on, are linked under same header. SGX favorable over OSE. You were looking for this? http://www.cmegroup.com/trading/equity-index/files/EQ-156_Nikkei225Revised_Final_Low_Res.pdf