Margot, glad that your new systems that we helped with have worked out so well!
Regarding the candidates you've listed above for your friend's system, although you are probably already aware of it let me mention that the X12 appears to have recently been discontinued. As you are probably aware it may still be available from some sellers, perhaps at discounted prices, but it appears to have been superseded by the X14, at a somewhat higher price.
Although I have heard neither the Brio R nor the Sphinx, I agree with Mapman that on paper the Sphinx appears to be the clearly superior choice, albeit at a somewhat higher price. Even at that higher price point, however, my instinct is to have some degree of skepticism that a component combining a tube preamplifier function, a 100 watt Class D power amplifier function, a phono stage function, and a discrete circuit (as opposed to integrated circuit) headphone amplifier, that is described as being hand-built in the USA and yet sells for only $1300 or thereabouts, would be of sufficient quality to do justice to the speakers. I say that despite a number of very favorable reviews I know the Sphinx has received.
FWIW, a relative of mine recently purchased at my recommendation a pair of Dynaudio X14's and a
Parasound Halo A23 power amplifier, available
here for $949. I haven't had an opportunity to hear it yet, but he is thrilled with the combination. As a power amplifier the A23 does not include a preamplifier function or a phono stage function, of course. He is using it with a no longer available and somewhat more expensive tube preamp that includes a phono stage.
The reference in the A23 description to "circuitry designed by the legendary John Curl," btw, is not hyperbole. John Curl has been a distinguished designer of very high end equipment for several decades.
If you and your friend were to choose a separate power amplifier such as that one, I have no specific preamp or phono stage recommendations to offer that are in a complementary price range. But I'm sure that a bit of research would disclose several good choices. The combined price of those pieces will undoubtedly be somewhat more than the price of the Sphinx. But I suspect that the additional investment would be well rewarded, and the use of separate components would also provide greater flexibility for possible future upgrades.
Regarding the CD player, both the Sony and any of the Oppo models would be fine choices. I have no familiarity with the Apollo R.
Best regards,
-- Al