Best Speaker for Ongaku

I would talk to Neli at Audio Federation. They have an Ongaku and will have experimented with many different combinations. However I don't think you could go wrong with Audio Note speakers as long as you have symmetrical corners in your room. They were made to go together.

Living Voice speakers such as the top model OBX-RW.

Apparently the Living Voice OBX-RW model is voiced to Kondo amps. 6-moons reviewer Edward Barker has auditioned these speakers with Kondo amps and considers the combo the best he has heard.

Budget, size of room and music preference?

right here on A'gon : Yamamura Churchill Dionisio 32 ....

Yamamura is great speaker but unfortunately too large for my room ( 7mx4.5m).