Eureka!
Mystery solved: I am now sure what I saw (and which was previously completely unknown to me until this very day) was a "second variation" of the FN 1905/06 which was virtually identical to the later Colt VP. Apparently only about ca. 30,000 were made (thank you, Google), compared to ca. 150,000 first variations, and the remaining third variations being produced to ca. 1,008,000. There is only a very small difference in the safety lever, but, since at the time, I didn't have a Colt VP next to it to directly compare, I didn't catch the difference.
Given those production parameters, they can be considered scarce, much more so than the first variation, and only made for a short time before being replaced by the "Triple Surete" model, which I had previously assumed was the "second variation," but was, in fact, the third. All of this occurred prior to WWI.
So, to those of you who said that Colt never made FN marked pistols, you were right. However, given the almost identical appearance, you can see where a mistake could be made. Anyway, I now have something "new" to look for.
It just proves that one is never too old to learn.
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