Newbie: power supply voltage and current requirements

Hello,

Being new to the group I'd like to ask for assistance with regard to
an appropriate power supply for the CNC router I've built. The motors
I planned to use are the Vexta PK-268M-02A wired as bipolar. At
bipolar the specs call out 6.3V at 1.4A; at unipolar they are 4.5V at
2A. The controllers are Centent CN0143 24-60V input and 1.5 -
14A/phase (these came with other used surplus parts; Geckos in the
future :) The breakout board is a Sound Logic Model M2 (Mach2).

What is the least voltage and current (for the PS) I should be
considering?

Could you recommend an appropriate power supply (parts, kit or
assembled) that would work for the above system? I've read where the
recommended power supply should be ~ 20x of the stepper motor
voltage. With the bipolar voltage at 6.3V and a max 60V at the
controller, even 10x is not possible.

Thanks for the help.
Mike