This movement, a bar style Swiss ebauche of 1845/1870 in my opinion, is advertised as 17j. This puzzles me a bit, I have at least 6 missing, and I was thinking that such movements do not go over 9. Could you kindly clarify the matter ?

Mario, it's a notionally better than the norm Swiss cylinder movement, Only because the upper cocks have jewels, very many of these were not jewelled at all, except on the balance.
The date range is probably about right, but I'd err towards the 1870's.

On the face of it, it appears the balance plus upper pivots are jewelled - except for the centre wheel and mainspring barrel, and I've Never seen these type ebauches jewelled in those areas.
I can't see the pivot for the escape wheel, but could assume it is jewelled.

It's unlikely that there will be any jewelling on the dial plate except for the balance and associated endstone, but you won't know without pulling the dial.
With all this in mind, I'd say it's a 7J movement, so it could be a 'typo' on the part of the seller - I'd mail and ask for confirmation.

John

Thanks, John. I was taking into account also a couple of jewels on the dial plate because the movement do seems to me "rich" in comparison to the average standard. Unfortunately the seller put a price tag too high, in my opinion, so that I didn't even bid ... and so we will never know how deep "richness" goes in that movement. I would really have liked to put fingers & loupe on "the dark side of the movement". There, sometimes, can be seen interesting marks & peculiarities.