There is also this Cortina on Ebay

This one is a clearer re-dial- the Cortina script doesn't look right and it has "Cronographe"- just like that re-dialed Silverstone we saw last year.

Where are all of these spare parts Heuer 1000 watches coming from?

The sheer number of these part-watches must cast doubt on the originality of the Blue herringbone Silverstone (which I note lacks the "Automatic" script above the dare dial), but I do think that the dial on the example pictured above is a step above these other obvious re-dials

David