If you look at pcpartpicker.com under CPU coolers, they have a lot of great filtering options. For example...
Here is a list of available CPU coolers that don't come with fans. Even at stock it probably won't be possible to find a passive CPU cooler unless you have some big fans for your case that are pushing a lot of air through, which from this post, sounds like you don't want to have. Most of the ones in this list are meant to be bought with the purpose of adding your own fans, in which case you probably want some quiet Noctua fans.
Here is a CPU cooler with one of the lowest sound ratings on the site. Scythe, while not a super well-known brand among most consumers, is known to be one of the best cooler designers with a good combination of quiet and performance. I put smaller model in my uncle's PC and it has been working great for him.
If you want the king of quiet and performance, you'll want something by Noctua. Here is a list of Noctua coolers sorted by how loud they are.
Keep in mind that these noise ratings/filters are not final and are subject to many other factors, like the case you have and if they're put into a PWM fan port on your MOBO, among other things.