I'm having a hard time wrapping my head around buying two straps for USD $300 without understanding what makes them supposedly special enough to justify the price. (Other than the buckle saying "Breitling", obviously.)
As with others, I especially don't think the Submariner+Orange is a good match, but it's not supposed to make me happy. If you have a black '57 on order, I don't think that would match in a fundamentally different way. The blue would be a good match for the blue '57 and the Rainbow '57? Good luck with that ;-)