The hole spacing is 1.5″ which is very roughly 38mm. The other measurements are a little vague because I don’t know where you are measuring from, but the offset (length of the foot from the upright) is 4″ and the vertical is 4 3/4″ from the base of the foot to the centre of the uppermost hole.
These are handed as well- the one that I photographed is a left hand one- and the part number is 9896LH.
It looks almost identical to the Trusty ones apart from the slight radius at the top to fit around the rotor shaft and the foot has a more gradual curve to it rather than the straight lines of the original. Otherwise it should fit with little or no modification.
Does anyone know where to find these today? I have one or two Earthquakes that I need to restore and so I shall need some new ones as well.