Simply buy the BTC, and when you have access to the BTC, simply withdraw the coins immediately to the US exchange. If you're going to send from an exchange, chances are, the withdrawal fees are going to be slightly on the higher side by default as to not take you too long to receive the coins.
How long would above step take? What if btc drop significantly like 10% during this process? It doesn't seem impossible for this scenario to happen.
That's the nature of cryptocurrencies (volatility), but I don't think with an hour it will drop significantly to 10%.
I vouch for Paxful here, a peer to peer basis, if you didn't afraid to fill the KYC process they are good to go. You can visit the site and do the math for the transaction cost. Or chose the given local exchange site above.
Or read this,
https://www.bitpremier.com/buy-bitcoins/china.