Should be close if not the same for the Camaro's I know 67's had a smaller shaft and a specific collar that it fit into as it goes into the door and this is a clear plastic, and the knobs themselves were color coordinated with the interior (blue with Blue interior, red with red etc...)
In 68 the shafts were larger, and had a chrome collar etc, and I think they dropped the color coordination. And 69 should be similar.
Get the chrome ones if you aren't sure the color will match. Chrome looks good on anything, plus the "ring inserts" into your door might be chrome anyways, yes?
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?