Hi Lemo
What country are you in ?
I am in New Zealand and use 2 companies here and 1 in australia for printing and casting
A company called Rapid prototyping in Australia is very good.
You need to output as an stl file at full resolution and there cannot be any errors in it.

If it needs repairing you can upload it to http://cloud.netfabb.com/index.php

you then upload your complete model to http://www.rapidprototype.com.au/ their system checks the stl for errors, calculates the cost of printing and casting in any metal you choose + freight and you pay with paypal (any sprues removed are credited back after casting)
Then it arrives on the courier 3-4 days then you can find a local jeweller to complete it.
cheers
shayne