203210873058 203244627368
For anyone interested, the Omega Dynamic band will not fit this watch. This is the correct brown band for it.
Very cool. Never really took notice of that model.
link goes to an expired listing.
https://watchcharts.com/listing/1686509/mens-mint-1975-zodiac-astro-ii-mystery-dial-automatic-large-17j-swiss
Here is the relist: 203210873058