I use central heating pumps. They are virtually silent and move a lot of water (3000l/hr) and have a good head (up to 6m). The flow at 3000l/hr is at a head of 1.5m, and the 6m head has a flow of 650l/hr. They can be fitted easily to standard plumbing pipe. The most silencing I have had to do it put a sponge scourer behind one to stop it vibrating against a plaster partition wall.
One of the best bits is that if you get Grundfos, and they break in the first five years, for any reason, they get replaced.
I second the call to have things plumbed in properly. It is nice to not be worrying about leaks.