I agree with both of the above posts: Matias Mini Quiet Pro or Leopold FC660C are both similar layout (although the Leopold doesn't have the F-key row) and also quiet. They each have their own switch feeling. The Matias uses an Alps-like switch, the Leopold uses Topre capacitive switches.
There are also a number of similar layout boards with Cherry MX switches, but the only way to really make those quiet is by modding the switches yourself. Mine (KBT Pure Limited Edition) is quieter than the rubber domes at work, but I've done a lot of work to get it that way (trampoline and latex mods on all switches, drawer liner mounted PCB, thick keycaps).