Longines Movement 12.68N Help

I am trying to identify the correct name as it appears on a parts list / part number which the sweep second hand fits to so I can source one missing from another movement. I have circled the part in the movement shot below. Any help would be appreciated.

I believe its called the second wheel. You may have a hard time finding one. If the pinion is broken you might be best getting the part re-pinioned.

They look like this.

Watch Second Wheel Replacement Second Wheel Super Durable Multifunction For | eBay

Thanks for the information. Movement pictured comes from a Longines G6B/158 issued to the RAAF I am restoring. I have a complete working donor movement which comes from an issued 6B/159 but stupidly used the part for another 6B/159 I had at the time. The original pictured above does not have matching numbers on the main plate and bridge assembly so hoping even though this one has seen some water damage that the second wheel can be salvaged for the donor movement but if not I will need to find hence the call for help

Here are the parts list for the sweep second mechanism, maybe it can help.

That's exactly what I was looking for. Thanks