This happens from time to time, they used to bring decent money because of it, but then the internet appeared and bottle cappers and bottle caps were able to be purchased cheap. So people stuck all kinds of things in bottles, refilled them and capped them and started swamping the market with them, especially Ebay because they hoped a sucker would believe the story of a ball point pen made in 1998 being inside a bottle made in 1968.
You'll find pens, machine parts, nuts, bolts and basically anything else you could stick down the opening in them, but yours does look like the typical fill tube from the bottle machine. For a little while people were capping Pepsi bottles with Coke caps, or Coke bottles with Mountain Dew caps, then they listed them for hundreds, if not thousands of dollars on Ebay hoping for a sucker to take the bait, sadly some did. Like Barnum said, a fool and his money as soon parted.
Enjoy it, it's a cool piece, and like I said looks to be the real deal...
