I'm looking to find my first Cow King's Set Item yet. According to Silospen Drop Calculator the set pieces can drop pretty much anywhere. I have already dropped super rare items like f.e. 'Griffon's Eye', 'Immortal King's Soul Cage' or 'Crown of Ages', but haven't found a single set piece from the Cow King's. I pretty much never farm the Secret Cow Level. So my question is: can you drop the Cow King's set only in the Secret Cow Level?