Yep, I'm with Fettcicle. Definately an LED/Lamp housing. The types that Radio Shack carries, although not completely accurate, will do in a pinch. Especialy since no one has discovered the true origin of this little bugger.
If you get one from RS, you can grind down the retainer nut, so that it appears round instead of hex. Otherwise the only other differences are that the red housing stickes up a bit further and is very smooth on the real one.
I post a pic of mine later ...
FP
**Edit**
<img src=http://image1ex.villagephotos.com/pubimage.asp?id_=1785719>
<img src=http://image1ex.villagephotos.com/pubimage.asp?id_=1785718>
<img src=http://image1ex.villagephotos.com/pubimage.asp?id_=1785720>