Well, just about any zahlamn is good. I have the 9800 aluminium version ( which is BIG, and still not the biggest ) but the more flat once are smaller. Look them up, since they make almost no noise ( at idle

) and they have awesome green leds ( if you get one with leds xD )
So yeah, for you I think the Zalman CNPS7500-AlCu LED will probably fit your needs ( still kinda big, what are the dimensions of "small-ish"?? ) and only 25 euro's here ( holland ).
Isocadia
Edit: Looked up some info, it should keep almost any AMD at 35 Celsius at idle and lowest speed. At lowest speed on max load ( crysis and alot of it

) it puts it on 50 celsius, still at lowest speed. So it should be fine. I think there is a full copper version, maybe that would keep it even cooler, don't know for sure )