A drug-dealing duo ran a Brooklyn-to-Montauk cocaine “delivery service” that catered to high-end Hamptons clients willing to pay three times the street price for a powdery fix, prosecutors said Thursday. Alexandr Dyatchin and Michael Khodorkovsky stashed cocaine and MDMA in Mercedes cars filled with “traps” — hidden compartments used for drug smuggling — and peddled those illicit wares to well-heeled customers on the East End of Long Island, according to prosecutors and a 74-count indictment leveled against the pair. “That cocaine was sold at basically three time the normal street value of cocaine,” Suffolk County District Attorney Ray Tierney said.

“So, it was a lucrative business for them until they were arrested.” The chic cocaine caper allegedly hatched by Dyatchin, 38, and Khodorkovsky, 44, was among five recent high-profile, but unrelated, drug- and gun-trafficking cases highlighted by Tierney during a marathon news conference. The duo was arrested Aug.

2 after an undercover investigation that included drug sales near Khodorkovsky’s apartment in Brooklyn, prosecutors said. Khodorkovsky had a kilo-and-a-half of cocaine when cops busted him, in addition to coke and pills stashed in his car’s “traps,” prosecutors said. He also had $38,550 in cash and 39 gold coins valued at $100,000 in his Brooklyn apartment, Tierney said.

Dyatchin’s rented East Hampton home had 589 grams of cocaine divided up into nearly twice as many individual packages, 269.