With your amount of winter chilling, you can grow a wide variety of temperate fruit and nut trees. Remember that the major fruit crops have had many cultivars selected to produce well in a wide variety of climates. Besides the fruiting scion cultivars, there are also rootstock cultivars adapted to different soil types. The best thing for you to do now is to get specific local information from nearby nurseries, fruit growers, garden clubs, and possibly the NI Agriculture department.
A few more thoughts that cross my mind: For best production fruit trees will need to be planted in full sun and I presume that will be the case at the edge of field. Unlike me, you live in a climate with year-round rain but you should consider an irrigation plan in case of drought, especially when the trees are small. That might not be a worry, but with climate change anything may be possible.