Not Beta. It was built by a small 'carrozzeria', but not officially. It's been proposed and sold as something else and in these cases the builder's name is kept secret. I found it after a long search and many phone calls. The same carrozzeria made another car, this time based on a 508c and it's quite nice. Featured here before, I don't think with the correct name, but I could be wrong and I could have commented there as well reporting the right name.