As someone that has been chasing '69s for over 45 years, I would be surprised if 10% of the 243,085 built survive today. As noted, up here in the rust belt they had rust perforation before the warranty was up. The average buyer was a younger person who didn't maintain a car, parked outside, got into accidents. There were always Camaros in junkyards back in the the 70s-80s. Between myself and a few other people I became acquainted with over the years, I would guess we easily parted out several hundred cars. There was a collector here in WI that that had 50-60 parts cars on his property; he showed me a shoe box full of body tags he saved over the years.
I have 1969 paperwork from a local dealer. They sold 10 Z/28s in '69; only one was still registered as of the early '90s. Of the 1,066 COPO Camaros in 1969, about half still exist.
10% would be 24,000 '69s. Between auction records, ebay data, other lists, there is a long way to go to hit that number.