Hello,
One of the biggest problems I see with these older Sony CD/SACD players is one day for no reason the laser fails. The bad thing is you cannot get parts or it was something else. I love Rega CD players but they have similar issues. So if you can get one of these ES models for $200-$300 knowing it could fail then go for it. I think you should pick one of the new $600 transports on the market like Cambridge and run it through your DAC. Another option are these older Oppo Blueray players like the BDP 83/special, 93, and 95. After the 95 people want big money. Oppo drawers have been used by Ayre, PS Audio, and of course the Oppo UHD205 which is awesome but is priced very high. I hope this helps. You are on the the right track.