Found this ad for the 1969 Cal-Expo in the May 1, 1969 edition of the Sacramento Bee newspaper from Sacramento, California. It states, "Chevy displays will include all models of their sports and recreation vehicles, including the sportsmen's dream pickup, Chevrolet Caribe."
newspapers.com
This 1969 date seems to correspond to what Gary L. Witzenburg wrote on page 62 of CAMARO! From Challenger to Champion: The Complete History. He stated, "very curiously, one so-called 'dream car' that made the auto show rounds early in 1969 was based on a '68 SS-396 Camaro. Dubbed 'Caribe,' it was a bright red 'dream pickup' with a headerless windshield, open-topped cockpit, targa-style roll bar and a five-foot vinyl-lined, teakwood-floored pickup bed replacing the back seat and trunk. It also featured a modified grille opening with small, high-intensity, G70 wide oval tires, with 'brushed aluminum sidewall inserts' on fifteen-inch aluminum wheels, high frequency flashing rear stop-lamps, and a hot beverage dispenser and cup storage box in the console."