Small tube amp for office suggestions?

I spend much of my day writing and online and play tunes in the background. (I admit its a tough way to make a living but someones got to do it.) I've got a Cambridge Audio integrated but am interested in replacing it with a tube integrated. Obviously, I don't need a lot of power and don't want to spend a lot to power background music.

My ideal is a tube integrated with a mute button and left to right speaker balance for a couple hundred or less.

Suggestions???