Hi kustomizer:
As Screwmachine and others have pointed out, your first step is going to be to find out whether it's an epicyclic gear train or an involute or some hand carved weirdass bastard profile.
I'd try to find someone who has a 50:1 Shadowgraph (optical comparator) and set up my gears on that so I can see the profile at some sort of reasonable scale.
Each profile will have a characteristic shape, and you can take a picture with your smartphone of the shadowgraph screen and post it for all to see.
The gear guys on here can tell you what it likely is, based on the picture, what it's part of, and the history of it, so take pictures of everything you can and post them all.
Once you've done that, we can have a more useful discussion of how you might go about it.
From there you can tell your customer what this is all going to cost and he can make a decision about whether it is worth it to him.
Expect the bill to be breathtaking if this thing has to be accurate in any way.
If best effort with a dividing head and a hand ground flycutter is good enough, charge him half a day to grind the cutters under the microscope and a day to fuck around with making some gear shaped bits and see if he bites.
If not, politely invite him to piss off and stop wasting your time.
Cheers
Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining
Whoops: I didn't read your post # 8 completely.
It sounds as though you actually do have a serious customer although what he wants with 65 copies of a 110 year old contraption I'm having a bit of trouble with; but whatever....
I'd spare myself the pain and farm this customer off to a proper gear maker if the requirements justify it and a hobby clockmaker if they do not, unless you have a strong personal desire to dive in and lose your ass.
Zahnrad Kopf springs to mind as a good resource, but so far as I know he's running like a one-armed paper hanger these days (correct me if I'm wrong ZK ).