Visiting wood factories

Hi Myself and my wife both need to visit Shanghai and Dalian next week. We are purchasing wooden flooring and we need to have a look at three different factories to decide where we are going to purchase from. We plan to leave South Africa on Tuesday. There is no time for visa application. What do we need to get VOA ? I am on a South African passport and my wife is on a Netherlands passport. Thank you so much. Regards, Michael