Great. sounds like you have some really good equipment. Then as a rule of thumb… subject to your own tastes… I would recommend looking at DACs and streamers in the $6K each range. The real trick is to get stuff that is of the same caliber… you have some good stuff… your source is really important. It is like a turntable and Phonostage… if you don’t start with it… it isn’t going to get better in the signal chain. I recommend looking at high end solutions.
I would see if you could find a used Aurender N10, and a good DAC… off hand I nothing comes to mind in that price range. But I am sure a lot of folks know of some.