I would probably put a coat of clear nail polish on it and let the air inside float it, trying to insert foam might result in misshaping and frazzling the end.
Here is something I put together a little while back. Not really much tying to it more sliding and sealing. I think this was a No. 6 hook, coated with Fabric Fusion and then nail polish, one coat of epoxy would also work well.
Beaded minnow.jpg