You could try claiming on your house insurance for lost keys. As I'm sure you're aware, to get Fiat to replace the red key will cost hundreds as a lot of the electronics need to be changed. If you don't replace the red key, you will be able to clone the blue key at locksmiths such as Timpsons for about £20, and its very unlikeley that you will ever need the red key.
But it will be more difficult to sell the car on without a red key, and you probably will have to drop the price (although Bravos aren't worth much any more!). Do something though - if your one and only blue key gets lost/stops working you really are in the doo!