I wonder if, having the watch for sale throughout the boutiques (I don't know, I'm just imaging it), it will be available also to anyone entering the shops. That would make the difference because 250 pieces are quite a lot and I don't know if a 5 figures price would be accessible to such a wide (if limited to the forum members) audience.
Edit
in house calbres could be adopted on a steel case:
-98XXX
-80XXX
-89XXX
-59XXX
Actually (my price list dates October 2012) there's one 89XXX for sale for the price of € 9.900 and that's the chrono spitfire steel.
So, my guess is. If the watch (I mean the model) already exists, it could be a spitfire, if the watch does not yet exist, we have plenty of choices, with probably more affordable price ranges.
In this case my guess is:
-A replica of ref. 431 in a human sized case, with cal 98XXX inside or
-A Mark with cal 80XXX inside.