That is interesting. The bottom one looks to me like a generic repair socket, as in keep your truck going because a reproduction of the OEM part is not available. Somebody cut out the old socket assembly leaving a rough hole, and the repair socket fits there.
If others don't chime in and tell you where to get the proper pigtail, I suggest post a want-to-buy ad in the parts section asking if somebody could dip into their stash of old wiring harnesses and cut that plug off for you. I've done that with success to get various parts and plugs for wiring harnesses. Or repair that plastic clip with
super glue and baking soda.