Recommendations for a "summer" amp?

Living in a hot southern climate I'm considering acquiring a 2nd amplifier for summertime use as a backup to my Pass Labs amp which runs quite warm. Solid state, cool-running, fairly recent vintage (don't want to invest in service) with a used price somewhere below $800. I had a good candidate in storage but I gave it to my brother so I need some recommendations. My system is comprised of an ARC tube pre and B&W Matrix 800 series speakers.
06-24-13: Theduke
"PSE Studio IV runs cool, sounds good! Perfect summer amp."

Yes, but where do you find one?
Thanks for the recommendations.

My listening room is on the west side which catches the worst summer sun and the hot amps just make the AC's job that much more difficult.
I think a quiet room fan obviates any tube amp issues from the heat sensitive among us, and a quiet fan won't disturb the experience any more than hearing Uncle Clem outside with your cousin Betsy screaming from the moonshine still behind the pigs. Merely moving the air around can really mess with the BTUs...swine British!