My 16 bore Darne is a V17. The Parisian dealer I bought it from insisted that it was a P17. He had a bunch of certificates on his walls attesting to his expertise and at that time I didn't know the difference. The only way it differs from a V19 is that it doesn't have a long tang behind the trigger guard and of course has only 7 stars.
I believe it might be possible to bend a Darne stock up or down. Remove the threaded screw from the wrist, bore the hole a bit wider and deeper and glue in a walnut plug. Make a jig that mates with the flats of the stock, secure stock to it using whatever means that will protect the wood, then use heat lamps over a protracted period of time with a steady pressure in the right direction. Afterwards, reinstall the threaded bolt/screw, whatever it's called, in the wrist. I haven't done it, am not about to do it but I think it might work.
nial