Loudness is a function of flow. There are no quiet fans, just low flow fans.
My setup uses a Panaflo M1A attached to a rheostat. Or it will; I was half way through soldering it together when I saw you post
Its pretty quiet at full speed and at minimum its very quiet (25 OHM rheostat, the Shack was out of 100 OHMs).
If you really don't mind noise or already have a noisy system get an H1A or even a U1A and use a larger rheostat. Then pick the noise/flow that suits you best.