Yeh most Meade and Parks Newts from days gone by had rotating rings.
Whats it worth. Here in Aus it would be hard to sell I would have thought.
But all you need is someone who wants such a rig and its sold.
I could not put a price on it here in Aus. But it would be worth posting in the CN forums to see what it maybe worth. I would do it in the classical scopes forums.
Best of luck with it.