There were 220k Camaros produced in 1967... Ratio between Camaro/Firebird, 2.7 to 1.
Base 326 was 250 HP 326 HO 285.
L67 RA package was $265 or so..

I would somewhat disagree on the cost factor of the Firebird being the reason they only sold 1 per 2.7 Camaros. If you look hard at the pricing of the Camaro versus Firebird, you will see little in the way of variances. Maybe $100-300 depending on drivetrain.

Reason Camaros sold better than Firebird? Camaros sold 7 months earlier than Firebird, were planned far in advance and had the hype, and were Chevrolet which was more prevalent in the market. Pontiac was little known in the "muscle car" market, exception being the GTO (to that point). I agree you could add in the cost factor as part of it, but not to the tune of 82k Firebirds and 220k Camaros.

Great read though!