What is wrong with the head? Is it cracked from overheating or from freezing? There are many machine shops which specialize in the welding and repair of heads and there is the possibility of getting a used head from one of the numerous dealers which frequent the forum. So no need to despair.
Welcome to TBN. The Yanmar forum is one of the most active and informed of all. We really like our tractors and have a dealer group here which is first class. In forum etiquette to write in ALL CAPITALS is the equivalent of Shouting or screaming, therefore it is best to use CAPs very sparingly. Sit tight and someone will come to help you momentarily.
Mike