Also here is an example of Dolan's nunchaku, including swivel chain models.
While there may have briefly been a time when Dolan's swivels alone sold for $100 during the early days of unregulated ebay, those times are gone. Without a regular market for them, it is impossible to establish collector prices and those devoted to collecting vintage nunchaku are a very small group.
I have bought incredibly rare examples for as low as $35 and I'd paid as much as $75 for a pair of 14" cocobolo swivel chain octagons. I have nunchaku so rare they were produced for less than 6 months but I'd have a hard time selling them for $35 because almost nobody knows what they are, fewer people care and there is no established collectors market.
But the history of the Dolan's U Swivel does make a fantastic marketing tool for Woodall's custom to sell "their version" of the Dolan's U swivel for more than $100.