2 x CR2032 Coin Cell Battery Box w/ On-Off Switch & Plain Wires : ID 4988 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits
AA Battery Holders with Switch/Leads
1 Piece 9 Volt Battery Holder Box PP3 9V Battery Case Clip With ON/OFF Switch Wire Lead Cover For 6F22 DIY Small Hobby Projects|Battery Storage Boxes| - AliExpress
2 x AAA Battery Holder with switch – Pimoroni
Led Lighting Set Battery Box With USB Hub Small Splitter Switch – Kyglaring
1 x AA Battery Holder with Switch and Leads - 1.5V | xUmp.com