I do not know how things work in Dubai but my experience of buying spare parts in other ME countries tells me that it is always a blind buy. The sellers would rarely tell you anything about the part you are buying as they themselves don't know. One can only make a guess from the model of the car if the part is worth the money. Why don't you get your present car engine overhauled at a good workshop with genuine parts which you will be buying yourself. In this way you are sure of the condition of the engine. An overhauled engine is as good as new one.