On the subject of unusual Patek Philippe Calatrava references, may I present a very unusual sculpted model: Ref. 5090J from about 2000, also called the “Russian Watch” due to its limited production for that market. I found two examples of this unusual reference for sale, so I thought I would take a moment to talk about it.
This stainless tonneau is a genuine Patek Philippe Calatrava but Ref. 3574 is beyond rare. I bet most enthusiasts never even heard of this model!