Quality RCA Switchbox

Does anyone know of a quality RCA switchbox that will accept several RCA stereo inputs and have one pair of RCA outputs so I can use several sources with a preamp with only 3 line level inputs?

Same question applies to digital sources; any digital switchboxes for coaxial sources that have a coaxial output so multiple coaxial digital sources can be routed to the single coaxial input of a DAC?