As far as I can remember, it was originally an IOR Quarter Tonner from around 1970, British designer, British built (despite the French-sounding name).
The racier version was called the Mystere Flyer, and the cruisy version even had an option for wheel steering /forums/images/graemlins/shocked.gif. Not many built. Very pretty hull shape for a '70's Quarter Tonner.
I know of two: one with wheel steering and deep keel; the other shallower keel and tiller steering. Not a lot of room in them by 'modern' standards but a lovely shape. Sailed well. Can send you some photos of one of them if you pm me a e-mail address.