I am also using Muse 02 for the low frequency pass filter of a DAC. It sounds really great in rich signal information and neutral. Tried few other expensive high grade Op-Amp with good comments but cannot replace it out from the DAC.
I remember one of my friend told me before, he has 2 pcs. extra. I shall ask him and tell you if it is still available. However, you are right, it is not too cheap, around HK$4xx- per pc.