So I've had a chance to consult Galizia, and some corrections and amendments:
1. there apparently was a Leonidas to the CP-1 spec. Leonidas was the only manufacturer that seems to have produced watches to both CP-1 and CP-2 spec. The Leonidas CP-1 used the Valjoux 222, and preceded the Breitling
2. Galizia dates the Breitling to "around 1975."
3. The Leonidas of course does not have a screw back, but the same 4-screw back as the Heuer Bund
4. Galizia illustrates a Breitling with a signed movement.
The bezel illustrated in the ebay sales listing appears to be correct, or at least the same as that illustrated in the book.

: I'm no Breitling expert, but the ref. 817 is known to me from an
: interest in military chronographs. It belongs to the
: "Cronometro da polso Nr. 1" or CP-1 spec, and was
: issued to Army Helicopter pilots, as the listing says, according
: to "Military Wristwatches, Sky Land Sea" by Galizia.
: In the two or three examples I have seen, movements are
: typically not signed. However, caseback markings are invariably
: present - it is not clear if they have been polished out on this
: one. It is smaller than the Bunds, the italian equivalents of
: which belong to the "Cronometro da polso Nr. 1" or
: CP-2 spec. The CP-2 are by Universal Geneve, Zenith and
: Leonidas. As far as I know, Breitling is the only CP-1, but I'll
: have to check Galizia again. For your amusement, here are my
: CP-2s - btw, screwbacks on both of them.

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