Useful to read the current situation with traced and untraced cars, I feel sure CF42 is alive and well hidden in someone's ( probably not a club member )garage as the renovation on her was finished in the mid 1980's by the person that bought her from me. He was quite elderly so I'm assuming sadly he is no longer around, so perhaps his sons/daughters still have the car if he didn't get bored with it and sell it. I suspect no more 'cobra conversions' will have been done in at least the last 15 years. I'm not sure any will ever be converted back to Fruas as the cost of re-lengthening the chassis and fabricating all of the unavailable body, trim/chromework, glass and interior parts would be prohibitive if not impossible.
Emmanuel, prices have suddenly jumped of certain cars in the States in the last 12 months or so, hence I guess in terms of rarity $ 300,000 is not insane for a perfect Convertible although I suspect he won't achieve that figure. I had no idea Maserati Mistrals could achieve that figure in America, in the UK you'd be very lucky to achieve anywhere like $ 150,000 for a roadster and $ 60,000 to $ 100,000 for a Mistral Fastback Coupe , I'm not sure about the rest of the European market values as they are of course left-hand drive like the USA.