Can't help with the value of this late 60s dress. Is it a dress or a top? It looks terribly short - I was wondering if it was a shell top that someone added fringe to? It looks like the sequins are missing or discoloured under her arms and where a man's hand would be if they were dancing. The only solution would be to replace the missing sequins, which is possible, but laborious and not worth the investment if you plan to resell.