Murph,
I re-read your
ORIGINAL POST on the Team Camaro site, and it really didn't give you a definitive answer to your question, so I can see why you're still confused.
For 68, the Door Lock Knobs matched the interior color of the car and are the same part numbers as the Astro Vent Pulls. For 68, the part numbers and colors (from the P&A 34, Group 10.559 or Group 9.262) are:
7799353 - Black
7759029 - Red
7759030 - Turquoise
7759036 - Blue
7759037 - Teal
7759038 - Saddle
7759039 - Gold
7759040 - Parchment
7759041 - Gray
7799354 - White
Note that the above knobs were also used on other models as well. The only one that was a "Camaro only" is the white!
Most people have replaced these over the years just because of the problem you're experiencing, "rub through". Although most repop houses only carry the chrome plastic ones,
D&R CLASSIC has a couple of the colors available. Do a search on "Lock Knob" and you'll get a few hits.
Ed