Definitely looks dirty silver to me! If you look at the bottom of the register, there might be traces of the clean silver.

Anyway, these are nice, comfortable watches and the circle and stripe insert on the Cal 15 Carreras makes for a distinctive dial. Possibly could be cleaned up a bit, but there's plenty of text in that area.

I'd say go and see it in person and if you're happy to live with the colour, use it to knock them down a bit and walk away happy!