...I bought the pistol used with the rear sight missing (I don't know why it was missing). The deal with the seller was that they would get in a new rear sight for me and fit it. Well, that didn't prove so easy. Where I live distributors for Browning/FN (Winchester, at the time) were less than enthusiastic in supplying a sight. When one was supplied it was incorrect for this model. So, after many months, the seller took the rear sight of a new BHP they had in stock and fitted it to my pistol. It taught me never to buy a weapon that needed parts up front. It's just too difficult to source parts here.
So, that field-stripped photo was taken when I was still awaiting the rear sight.
Here's the pistol with the sight fitted.