Vox part number 09-301-0. This open gear tuning key was fitted to a number of early Vox solid body models: most typically the Clubman and Bassmaster basses, but also early versions of the Ace, Clubman guitar, Soloist, Duotone - guitars with the early elongated headstock, rather than the later Fender-style.
See some of the examples here. Both guitar and bass models used the same part.
This tuner requires no routing, it is simply held in place with two screws - though the extrusions on the underside of the unit do create some minor indentations on the headstock.
Dimensions:The foot print is 35mm x 17mm, with a 6mm diameter post, with a 7mm post hole in the headstock.
List of Vox bass machine heads
List of Vox guitar machine heads
$30
$55
$40
$65
$230
$240
$270
$200