NEM is now available for exchange at CoinSwitch. It can be purchased at best rates from https://www.coinswitch.co/exchange/btc/xem/0.1.
About CoinSwitch: CoinSwitch is the first cryptocurrency and altcoin exchange aggregator. They have integrated many leading exchanges across the globe like ShapeShift, Changelly, BlockTrades to provide best exchange rates to their customers. Currently, they support over 100 cryptocurrencies and more than 4500 pairs to exchange.