Speaker part is the same for Raspiboy RetroStone and RetroStone2, but cable is different between versions. Choose the correct version you need.
Raspiboy version speaker is compatible with the 8BCraft PCB. It has 10 cm wires with a 2pin JST PH 2.0mm pitch connector.
RetroStone version is for RetroStone.
RetroStone2 version if for RetroStone2.