This has been to my watchmaker for some internal TLC. He told me what I already knew... It has the simplest of ETA Valjoux 7750 movements. No Breitling branded parts at all and 17 jewels. This is correct for this early type (of this generation - beginning in the mid 80ies) of Chronomat and further enhances my hunch about this watch as an honest one owner (full set) watch - as many of these were modifyed at services with branded parts, 25 jewel movements, etc.
Enjoying my morning constitutional on this lovely September morning, sorry to hear that you boys down south seem to be having it a bit damp at the moment.