There is Conacado which is certified fair trade and some of their beans are organic. They have both Hispanola and Sanchez. They are supplied by 8 smaller farmer blocks or bloques. I have close contacts with the one in Castillo. The factory in San Francisco de Macoris is called Cafriesa and makes paste, butter and cake, two of their clients that I know of are Equal Exchange and Green and Black's. I have some friends who work with Conacado and Cafriesa and their processing of paste is improving. The guy who would get you samples is named Abel Fernandez and he speaks decent English. Their info is on their websites. I can also put you into contact with the farmer's cooperative near Nagua that supply Mast Brothers and Taza. One of Conacado's bloques broke away and formed Coproagro. My brother-in-law sells most of his cacao to them. There are many others including my wife's extended family. I would recommend a trip during the November/December harvest, even if it is for a few days. I am getting started myself and am willing to help anyway I can. I am a high school teacher in NYC but am transitioning into chocolate over the next year, maybe two.
I visited a variety of farmer's cooperatives the last few summers and met the people Mast Brothers and Taza source from. I was also translating at a chocolate factory for a USAID consultant working with Equal Exchange and have close contacts there. My wife's family also produces cacao and will be working with them to ID quality beans, improve fermentation and drying, and then work with a women's cooperative to make a quality paste. Let me know how I can help.