Well (off the top of my head), if I were gonna have a crack at something similar, I'd get me one of those 'syringe pens', and head off to Maplins - or in the US, Radio Shack, etc.
Various connectors, Coaxial or TV aerial plug, BNC, Phono, RCA, etc have different knurled sections, that would make great Victorian / earlier Steampunk-y control knobs and such. As a bonus, they often are available as gold plated, which would look really cool.
A Dremel would quickly seperate the knurled ring, etc, from the component part, such as a BNC connector.
A look around in a stationary store should net you a steel ink refill tube that would serve for a writable 'needle'.
Removing the clicker pen tube from the syringe would allow you to add a plain fashion jewellery ring to the top of the barrel (or something), and a metal sleeve (maybe a pen tube?) over the plunger, which you top off with a small drawer knob or button.
Glue (or just jam) the ink refill into the nib of the syringe pen, and use a short piece of metal tube (perhaps part of an extendable antenna) to hide much of the length, and butt up to the nib section of the syringe.
Use a silver jewellery bead where the ink refill comes out of the tube to disguise the join, and half of an oval shaped one on the barrel.
Ya might find a connector that would work better for this.
Kinda like this, but with less crappy visuals:
D'oh! Tube on the plunger should go into the barrel!
Sorry for the 'blah' but I gotta work it out as I go!
Cool prop, by the way.
C.
