Jean Pierre Kelbert (JPK) is a fascinating guy and one of the more knowledgeable boat builders I know. He does not only build performance boats and racers from many years as he was himself and accomplished solo racer besides he is used to tailor made rigs to the needs of each top racer (solo) or crew.
He can not only make anything you want as he can give you valuable advice about everything that is sailing boat related. You will understand better your needs how they can be satisfied and the better options regarding the boat, keel and rigging options after talking to him.
He is a passionate guy and someone with whom it is a pleasure to talk too. If you are interested in the 38 or that kind of boat I advise you to contact him and go to Lorient to have a talk with him. Even if you don't buy a boat the talk what what you are going to learn from him deserves the voyage.
He will explain everything about the different keel options. I suspect that they are not making more /or any 38 with a swing keel due to extra costs. probably that will add 20 0000 euros to the boat price.
And if you go there, please post here what you have learned