If you're crazy... you can do this on your own. Here's what you'd need to do...
1. Create a mold in the correct scale - most likely you would have to carve it yourself. You could invest in a 3D model and send it out to one of those rapid prototyping shops to have one made into a solid material.
2. Make a vacuum forming table
3. Use the new part as the mould for the plastic
4. Cut out, paint, attach.
That's it. Once you have the mould everything else is easy.