For South Korean companies to send rice this is a nice gesture, but a defeat for the North Koreans. I have always felt that the country can be fed with legitimate imports of goods from neighboring countries in significant and meaningful amounts. Also, there are enough wheat seed supplies and agricultural specialists in China who could come in and kick start the economy. If anything these aid organizations can shame the government into doing something. But, I also think this is just a band aid.
Chinese companies buy cement, sand and gravel, steel, silk and chemicals heavy industrial items.
For consumer goods, the North Koreans have very good pickled cabbage and traditional Korean foods, and liquors. I have also heard they have a great beer. On a large scale, they need just about everything. But, on a small scale, there are lots of micro opportunities. They love Cadillac's.