I have no experience in 3d at all, and tested shapeways' conversion tool from a 2d logo. After 2 unsuccesful attempts at correcting the model myself, I would like to ask someone to take care of it.
Attached is the output with errors. I can send the 2D .ai file to anyone interested in taking this on. The only other requirement is that the ring on top to put the cord through be perpendicular to the body of the pendant (spun 90°)