8 x AA battery holder with 5.5mm/2.1mm Plug and On/Off Switch : ID 875 : $5.95 : Adafruit Industries, Unique & fun DIY electronics and kits
12V AA Battery Pack - Battery Case with male 12V plug - SSS Corp.
Amazon.com: FolioGadgets 12V AA Battery Pack with Leads, 8 x 1.5v AA Battery Case Holder, Battery Storage Box with ON/Off Switch 6inch Bare Wire Leads [4-Pack] : Tools & Home Improvement
LED Battery Holders | 12V Battery Holder for AA, 27A, 23A LEDs
Amazon.com: FolioGadgets 12V AA Battery Pack with Leads, 8 x 1.5v AA Battery Case Holder, Battery Storage Box with ON/Off Switch 6inch Bare Wire Leads [4-Pack] : Tools & Home Improvement