Hey Roc, remember I was telling you that I was gonna make some light-weight epoxy formula (filled with micro-ballons) for making prototype plugs. Well, I finally did. I made it so that it handles like a putty.....doesn't stick too bad to the gloves. Basically, it's a two part system with a 1:1 mix, although the ratio isn't very critical as long as it looks close. I mixed some up last week, kneeded it like cookie doe, then rolled it in my hands into a shape similar to your pencil poppers pictured above (the one I made is about 7" long). I cured it and gave it a quick sanding. It's already water proof so it needs no additional sealing.
Since I've never built plugs for stripers, I was wondering if I could send this cured specimen (or even several) to you so that you might give me some feedback on its lightweight properties, it's strength relative to further processing (adding hooks, weight?, eyes, ability to accept paint........). I'd also be interested as to whether you think it would require a wire through type assembly or whether the stuff is strong enough without using that approach.
Any feedback that you're willing to provide along those lines would be most appreciated and help me tailor the formulation further.
Let me know if you have any interest at all in pursueing this with me over the winter and perhaps we can have a phone conversation to discuss further and go from there.
I have an idea for making a slithering eel as well.