It's 1965. The Flintstones was in its 6th and final season. Bewitched was in its 2nd. Someone, either at ABC or Screen Gems, which at the time was distributing Hanna-Barbera's programming, decided to bring the two shows together, by concocting a 1-shot storyline that had Samantha & Darrin Stephens (Elizabeth Montgomery & Dick York) moving pro tempore to Bedrock. H-B already had the character designs, since they provided the animated open to Bewitched.
To my knowledge, this was the only toon credit for York and Montgomery. And while reruns of Bewitched would emigrate to ABC's morning lineup, running six days a week at one point (!), apparently, no one thought to follow up on this experiment by creating an animated version of the series. The only other cartoon associated with the franchise was a Saturday Superstar Movie that featured Tabitha & Adam as teenagers, and this was right after Bewitched had ended its run. It's a pity. Anyway, Wilma (Jean VanderPyl) & Betty (Gerry Johnson, who'd taken over for Bea Benaderet in season 4) get acquainted with "Samantha":
I am not entirely sure if this episode would be included in the Flintstones rerun package that aired on NBC while Bewitched was still on the air. We do know that it aired in syndication, though.