Walter Umland did the Stiletto 660 and he may have one available, or some one else may want to part with theirs. Usual powered with a St.51 or similar, but I imagine you could squeeze a .60 into it. I think that was the largest Stiletto that was Les McDonald. Or you could just take any .60 size stunter and build the fuselage and wing tips to the desired shape.
Type at you later,
Dan McEntee