I used a 69 with AC as a parts car and the remaining body was chopped up. The thing was beyond repair due to rust. I still have some of the AC parts laying around. My 72 didn't come from the factory with AC. If I decide to install AC later on I will go aftermarket as most of it fits under the dash and out of view. A lot cleaner installation.
GM never installed A/C on any car with a mechanical lifter (after they learned not to do this from replacing lots of warranty claims with the HiPerf 348 and 409 motors). If the car was a COPO you could order anything you want (that is what a COPO is a custom order), but few wanted A/C as most were hot rods with little to no though about creature comfort. So you can cross off all HiPerf engines from the production list.
Approx. 251,849 Novas were produced in 69 with about 28,939 of them having factory installed AC.
In the 60's it seemed only the high end cars like Cadillac, Olds 98 and such had AC. I remember when my parents bought their 66 Olds new it was the first car we had with AC. 2 years prior we got our first color TV and they didn't get the remote tuning option either. Folks back then didn't pop for the hi dollar options like they do now.