Sabby is right, but you are forgiven on a first attempt - welcome!
Have you ruled out the Rega fono mini, which is maybe an even more obvious choice with the RP3. That said, either phono stage pre-amp will work fine with the amps you mention. Are you buying them secondhand, as I think both are discontinued now? The NAD would be my choice, and Cambridge do much better ones now, but it depends on your budget. That said, why spend £500 on a great TT only to strangle it with a modest amplifier?
The 9.1 are great value, also superceded but still very worthy.
So, in summary, all these will work OK, but you are underplaying the Rega unless you budget around £500 to £800 in total for amp and speakers.