Strange. The footnotes in my copy refer only to a) similar designs "jedoch ohne Liktornebündel," b) same designs but with the overprints of the so-called Repubblica Sociale, and c) three designs with attached "Reklamefeldern" (advertising labels) of 1924/5. There's no reference to #641, though that is, chronologically, where my stamps ought to appear but don't.
Curiously, on that same page there is a footnote that says: "Marken mit Propaganda-Anhängsel von 1942 und Aufdruck siehe bei Marken mit Reklamefeld," i.e., "For stamps with attached propaganda labels of 1942 [my stamps!] and overprint [not mine] look next to stamps with advertising labels." But, no, other than those with advertising labels of 1924/5, there's nothing there.
So, did Michel remove all reference to my stamps in its edition of 2001/2002? Without a note saying so? Not likely. Instead I suspect a layout or printing error, that left a blank space where these stamps with wartime propaganda labels were supposed to be.
Thanks in any case to those who responded. You have provided the catalogue numbers that I needed. Michel, I assume, has corrected the error in subsequent editions.