Well, you'll have to tell them what's your buy-in price if you want to convince them that its a viable product ! :d
The SBGA031 is already very close to what you're looking at, the Spring Drive being superlatively even more accurate than a hi-beat movement. And its already a 200m rated diver.
But yes, understand the appeal of a hi-beat due to the assurance long-term serviceability even from 3rd party sources.
