The original Radeon 64MB VIVO didnt run terribly hot when clocked at it's default 183/183, the fan was more for looks and to give the appearance of being a high performance card then for actual necessity.
As long as you don't intend to overclock, and your case isnt extremely hot to begin with you should be able to get away with just a medium HeatSink alone, and forego any fan altogether.
I definitely wouldnt overclock if you plan to go that route, but at stock clockspeed it's definitely viable.