Hi Sharynideas...... I'd just copy and past a pin, then I'd mask over it and just paint back the end with the head, skip the middle section and paint back the pointed end..... add a little shadow and, viola..... here's a link to some pins that would be perfect.... over at Stock Xchange..... it's free....
http://www.sxc.hu/photo/795397
Beth
Oops..... sorry, molecule..... just saw your post.....