I've used Shapeways to make parts; they can print Nylon (among many other materials).
Craig, there's also an online service called 3D Hubs where people with printers host "shops" so you can select based on their prices and services offered. It's also nice since you may find a local printer where you can pick up a part to save on shipping.
I can assist with printing if you have a file that is not copyrighted.
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