Tube pre amp for Blue Circle BC 22

Hi, i am looking for a tube preamp for my Blue Circle MK 1.

Right now i am running it with an Audio Note M-zero, but i am so certain that this is a good match. The sound is a little thin and i have the feeling that i am missing som magic.

What i want is a better match and a more tubey sound - not to say that the sound is real SS like but i am looking for a better result.

Gilbert at Blue Circle recommended me the BC 21, but it is too expensive and hard to find used.

Does someone have a opinion what budget tube pre amp to look for and what could be a good match?

Thanks, Johannes, Denmark