Reading between the lines I might assume you don't have facilities
or experience to make this design. I would suggest you develop a
relationship with a local trade shop, the kind that does repairs etc
for your local jeweler. In this way you will have immediate feedback
regarding the feasibility and costs of your ideas.
Honestly, most manufacturing concerns probably will not want to deal
with the occasional one-off from someone they don't know. They are
geared to quantity production and repeat customers. This doesn't mean
you cannot find a maker to suit your needs, though, but it will take
some looking and (maybe?) some false starts. False starts drain your
Either way you'll need to appear as a professional. Get a tax number
etc etc. if you haven't already. Without all the official hoopla they
may think you are a retail customer and charge you accordingly.
One resource for manufacturer leads would be the JCK industry guide.
If you can't get a copy email me and I'll photocopy appropriate pages
for you if you give me some parameters of the work you want done.
best of luck