[DonVoigt]

I should have said grip "strap", which is not shown.

The pictures are not good enough for me to see what is "different" about the sear safety, they are not all identical on German pistols.

So if it is not too much trouble, just what is "sedately" attached? Is it not riveted?

The length looks to be the same as others. if you would measure the length, then I could compare it with some of the 40 or so German police pistols with sear safety that I have.

If you have the "Official guide to Gunmarks" by Byron, you will find several Belgian proof markings, the one shown on p 124, is similar to yours(it is a drawing not a picture). That style/design proof stamp has been used on guns of foreign make, proved in Belgium since 1921.
The proof house is located in Liege, hence the "L".

I know of no one who collects Belgian police pistols, but Anthony Vanderlinden is a Belgium expert, and you could PM him through the boards.