Junction box or switch box

My husband has two mac desktop computers. A new I mac which he uses for his sermon writing and the bulk of his communications, but he also has an older model that he still uses for a baseball statistics game he loves playing, but the new iMac will not support. So I want to fix him up with a switch box so he can connect the printer, stereo, and other accessories he needs for his recording studio and then switch from the old computer back to the new computer with one switch or remote. Since the new mac does not have all the inputs needed for his recorder and the piano keyboard. I would like a device that has at least one mid in and several USB ports as well as RC inputs. I don't know if they make them with mic inputs but those would be nice as well so we could connect a sound system to the mac. Thank you.