Unfortunately Video Connection are no longer selling 4 way Wico joysticks. They still have a few, but they are keeping their remaining stock for renovating old machines (at least that's what they told me...). They are also no longer selling red ball Wico joysticks, presumably for the same reason.
Does anyone know where 4 way Wico joysticks can still be bought?
With regards to dimensions, as far as I am aware Wico joysticks came in only two sizes. The standard joysticks had a 3.5" shaft (measured from bottom of shaft to bottom of ball handle). There was also a longer 4.0" length shaft available. I understand the longer shaft joysticks were used in Robotron cabinets.
I recently bought some black and blue 8 way joysticks from Video Connection. I did not ask for a particular length shaft. The black ones that arrived were 3.5" and the blue ones were 4.0". I believe it would be difficuly to mount the 3.5" joysticks in wood unless you mount from the top.