To be honest, I bought the 550ti as a temporary card until the 600/7000 generation. I'd rather not spend money on a cooler for it because it's slow and temporary.
I can get a CM Silencio 550 case locally, but I'm not sure if the Hyper 212+ would fit inside? I don't think that heat would be a problem for my system with that case, right?
According the CM website the Silencio 550 supports a max CPU cooler height of 154mm, and the 212+ is 158.5mm, so that would be a no.
You would likely need a video card with a blower type fan exhausting most of the hot air out the PCI slot since the Silencio 550 only has a single 120mm exhaust fan at 800rpm. These cards (particularly nVidia) can be quiet, but generally not silent.