Check whether you mean the original Parrot charger or a third-party multi-charger, since the larger packs need a bit more output than the standard one. Parrot's own accessories are getting harder to find new, so I'd look at reputable hobby retailers or resellers that list the part number on the box. Before buying, confirm the connector type and charge rate match your pack, and be cautious with unbranded listings that give no specs. If you still have the manual, its accessories page usually names the correct charger model.