I’ve only seen one of those in person. They sure are nice to look at. IIRC, it was most likely made in 71 and 72, and was probably available up to about 74, 75, until dealers ran out of all of them.
Unfortunately, the C riser was the least sought after. Good ones will fetch around $400. to $600. The uniqueness of the Blue one may add some to the value, and the condition looks exceptional too. That’s all just a guess, and if you find a collector who “needs” it, the sky may be the limit.

"Archery is really very simple. You just have to do the exact same thing on every shot"
Bill Leslie, July 22, 2017
"Form is everything."
Al Cole, June 7, 2008