Difficult issue ! Most true Class A amps are low power. Less than 50 W. The High power Class A amps are also very high priced. Even a previously owned one. Then there is the issue of tubes vs. solid state or even a hybrid.
I'm not clear on what your intention is as far a speakers is concerned. Are you planning on re-configuring the Personas to use with the two channel system.? Basically, there are a lot of things to consider here, all of which would have a significant effect on the outcome of the project. Also, it's almost impossible to audition something on the used market. Building a new 2 channel system; - - - I would have to say that there are many fine amps on the market that could be candidates, including the SCHIIT amps and pre-amps. Excellent reproduction capabilities for a small amount of money, and you wouldn't have to fool around with someone else's previously owned discards. Make certain what loudspeakers you intend to use and pay careful attention to how they might sound driven by different amp technology. Then of course there are speaker cables and interconnects to consider. I have found that the average audiophile ends up going around in circles for great periods of time trying to solve the mystery of matching components, and stay within budget restrictions. Also, I am not certain that simply going to a pure class A amp will yield any significant "magic" without other system elements fine tuned. I'd also look at good class A/B amps.
I'm not clear on what your intention is as far a speakers is concerned. Are you planning on re-configuring the Personas to use with the two channel system.? Basically, there are a lot of things to consider here, all of which would have a significant effect on the outcome of the project. Also, it's almost impossible to audition something on the used market. Building a new 2 channel system; - - - I would have to say that there are many fine amps on the market that could be candidates, including the SCHIIT amps and pre-amps. Excellent reproduction capabilities for a small amount of money, and you wouldn't have to fool around with someone else's previously owned discards. Make certain what loudspeakers you intend to use and pay careful attention to how they might sound driven by different amp technology. Then of course there are speaker cables and interconnects to consider. I have found that the average audiophile ends up going around in circles for great periods of time trying to solve the mystery of matching components, and stay within budget restrictions. Also, I am not certain that simply going to a pure class A amp will yield any significant "magic" without other system elements fine tuned. I'd also look at good class A/B amps.