Hi luka,
it is possible to use the EA-BL08 with the following modification:
There's a small plastic nose on the left side of the EA-BL08. Only
the SL-C750/760/860/3000 have a spare for this. So you need
to cut the nose off, then the battery fits perfectly.
Cutting the nose will not affect safety of the device.
Also you need the EA-BL08K, where the "K" stands for "Kit".
Kit means, that the needed black battery cover is included.
///TRIsoft
Marc Stephan