Hard to say for sure, but I imagine that given it's a SoC there's no standard HSF for the C3000 atoms. The supermicro board I have uses the same heatsinks as most of their Xeon-D line however, so many of the coolers suggested in those threads should also fit. However IIRC I think only a couple of them would fit in a 1U case.
FWIW the HSF on my A2SDi-8C+-HLN4F is "quiet enough" as long as the fan can be kept under 3000rpm (and OK-ish chassis air flow should suffice) depending on your usual load (mine is never stressed on more than a couple of cores). If you've got a model with only the heatsink you'll likely need high chassis airflow to compensate and in 1U that usually means screamers, so you might consider the SM HSF if it fits (no idea how to find the part number I'm afraid).