Well, a certain guy who I believe to be very knowledgeable about Maserati history tells me that the car is a fake. That's not clear to me from the Coys description. But I believe the guy, (an F-chatter who doesn't post much anymore). I'm hoping for more details from him.
If you read the link carefully: it says "copy" at the end ;-). http://www.coys.co.uk/cars/1959-maserati-tipo-6061-birdcage-copy