...to collectors, especially the $25 Holiday Casino
chips (N4661-NCV) that were later used at the
Harrah's Training School.

I had a bunch of the "original state" HUB (N4660)
and SCA (N4659) inlay chips (no NCV overstamp) that
I sold out at $500-per set (several years back) when
the training school material was being circulated at
$80-per chip.

JB