TruConnect 3 Pole Box Style Jack Socket

TruConnect-6-35mm-Switched-Jack-Sockets-TruConnect-20-1397-p-A-standard-6-3mm-frac14-in-box-style-switched-3-pole-jack-socket-with-2-poles-switched-upon-insertion-of-the-jack-plug-p-TruConnect-3-Pole-Box-Style-Jack-Socket

Price: 1.30 from Rapid Online Rapid Electronics Ltd.