Rahul, I guess you will have to get them from HK (Hobbyking or HongKong). It's probably a novelty item
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You could probably change the DB connectors to 4.0mm bullets and insulate it properly to work with both the batteries. Like Salam suggested, it is wiser to change the connectors on the board if you have multiple batteries (which you will have soon in this hobby). You can use heatshrink to insulate; Electrical tape will give way due to the heat of the junction.
Hope that helps
GS