Dual 604 anti-resonator (counterweight) problem

I have a Dual 604 where the felt pat has fallen off inside the anti-resonator.

There are plenty of pictures available on line of what broken units look like. Even a few pics of best guesses about how to put it together. These pics and posts show more than one idea about how this is held together.

Does anyone have a lead on how this should look before it falls apart. First hand knowledge or a pic of the actual item.

Thanks in advance.