I don't think there is a part number, but here are the pics of it. It's just called the "LCS Buss Termination".
I think that is a tantalum capacitor connected to two pins side by side. I cannot read the value. I think the wire is just a way to pull it out of the connector you put it into. It looks like it's between +5vdc and RCV
The LCS connectors are the Molex Pico-Spox 1.5mm connectors. Molex 0874390400, the pins are Molex 0874210000. I crimp them with the Engineer PA-09 Crimper, the same tool I use for most Lionel and MTH connectors.