You need 1.5 to 2 times bigger idlers, or phase converter than machine. This can be done in stages to save costs. Example start a 5 hp converter, then just a 10 hp. three phase motor. Building your own phase converter is a doable project. Look in to tuning voltages with run capacitors
On this side of the pond, you'd need wiring and circuit breakers for a 40 amp circuit to run 7.5 hp.
EDIT. PS>. I don't know this machine. If the spindle is a three phase motor, take a look at a 10 hp. VFD to run your machine.