Just treat them (and comparison price them) like a Tama kit of the same period. There's no collector cache within the Camco collector community but maybe the Tama people will be fascinated.

And "rare" can be just another way of saying "not popular at the time they were made".

They're probably fine drums.

Scarce, rare ... wha-evah. I'd pay 500 for a good used Tama set, in fact I have done so and was not sorry. For this vintage, and with the not-so-common hardware (very cool) and I'm pretty sure they'll sound good, I'd def go for them.

Then again, I'm sure some people would laugh at my decision making process. There is a difference for me in purchasing something I'm surely going to keep for awhile vs something I'm not so sure about.

Best of luck with your decision.