It's hard to tell but it looks like it's a 4-digit serial number with a "D" prefix, which I believe is post-war. The grip is replaced, that could have helped since some later commercial ones had a Winfield Arms Co. (WAC) logo. But from an old Gunboards thread, which supports my remembries, this is a mid-50's pistol.
"The D-prefix pistols are most likely surplused from the French Customs Service (Direction générale des douanes et droits indirects (DGDDI), with the customs agents commonly called douaniers), and your pistol probably dates to the 1950s. (What does your slide legend say? -- Your pistol is from around the time the MAB D slide legend changed.)"
One question would be if each agency got its own serial block starting from 1, like FN did on pre-war contracts. I highly doubt it, I can't see some of these agencies all getting 3-4k pistols. But maybe they did... There also seems to be two types of serial numbers in these low ranges, one like this (and your PM) where the s/n is "virgin" on the frame and one where the old serial was milled out and re-stamped.