The little three-wire one looks promising. Red is 5v and probably yellow is ground. You need to test that with a meter on beep (continuity). Put one probe on the battery black wire where it goes into the controller and the other on the yellow one. if it beeps, that's a ground (0v) and the other is the signal wire. Any throttle will work, but think about which type you can fit considering what space is on the handlebars. Throttles normally have a red wire (5v), a black one (0v) and any other colour, like green, white or blue, for the signal. If it comes with a connector of the same type, check that the wires are in the right sequence before connecting. If it has the wrong connector, cut both connectors off, join the wires and insulate them.