Help Tube Newbie with amp selection

Hello folks-

Looking for some general advice on matching up tube amps (monoblock perhaps) to my B&W 802 ser3 speakers. I know these are power hogs and I have always fed them SS power but I would like to try tubes - unfortunately I don't quite understand the power ratings on tube amps - what am I exactly looking for (wattage wise) to power the 802s to get them to sing properly? Not looking for deafening levels, just enough for mainly classical in a 12' x 15' room.

I have a friend in Hong Kong who can obtain most of the chinese-made tube amps at discount so i'm hoping to try some of these out (ie. Consonance, etc.) Any recommendations?

Thanks in advance!