The best sources of fats are any real foods, made without excessive factory processing so eggs, real full fat cream and Greek yoghurt, unprocessed cheese, any meats with fat on or in them including proper butcher's sausages and bacon and decent quality salami, olives, nuts, avocados, olive oil, butter, lard, coconut oil, oily fish and probably much much more. The key is to eat Real food, so avoid margarine, "lite", "low fat" products, seed oils, spreads, and anything that, quite frankly, looks processed and unreal.
Sally