Bluesea just showed us a pearl and zircon set on another thread. He designed and manufactured it. He uses CFWP, vermeil, and zircons to keep the cost down. Maybe he can design you one. His looks runway ready. I am saying this without knowing if it is possible, he is a new member and we are just getting to know him.
If you want the best pearls, try a really well known pearl seller. Someone like that might also have a designer who can make the metal and diamond parts very similar.
I am going to recommend Pearl Paradise, because it has top quality pearls, including the absolute top quality akoyas, which are certified under the strictest standards by a Japanese lab. I am almost positive PP has an in-house designer who does the metal and diamond parts of his jewelry.
If you want to see what the top quality freshwaters look like, go to PP. They are the roundest you can get, have luster comparable to the akoya, and cost a fraction of the akoyas.
Would you mind sharing the price of the set? Sometimes pricing tells you a lot. You may be able to get a reduction in price by confronting him with his foolishness, then just change out the pearls when you get it.
just my 2cents. I hope you get what you want.