Both boards will work with a "standard" 24VDC INPUT VOLTAGE, so a 24VDC power supply is one part of the equation. The next is how much total power (P=VI) is required for the steppers, so I just added up each power rating plus a bit and got to 10 amps (this is only for the steppers mentioned, and would not allow the drivers to be used in parallel to their maximum rated load which would be approximately 458W).

One of the drivers is rated to 4.5a and the other to 5.6a maximum output (but as I said, the steppers don't need anywhere near that amount individually).

It is probably cheaper to get a 24VDC @ 15A than 10A, there seems to be a lot more choice. (If you want to push the drivers to their max rated load you will need approximately 24V@20A supply)

So 24VDC @ 10A should do as required, but 24VDC@20A will allow the drivers to run at 100% rated load.