Try TRL (Tube Research Labs) I know they do very good work on newer Sony machines.
Best place/person to upgrade the Sony CDP-707ES
I have a mint condition Sony, CDP-707ES; beautiful, bronze, wood end caps, not a scratch on it. As I am reading more and more, I have realized it has sort of a cult following, and there are several people and/or places that deem it worthy of modification. I would like your opinions on the plan itself, and who you would recommend to perform the upgrades.