

You can get the part from Tom.B's shapeways store here:
First set:
http://www.shapeways.com/model/564196/c ... a-2-0.html
http://www.shapeways.com/model/564197/c ... b-2-0.html
Second set:
http://www.shapeways.com/model/564205/l ... a-2-0.html
http://www.shapeways.com/model/564209/l ... b-2-0.html

