Lola Flores, a dark-haired, deep-bosomed Spanish flamenco dancer with a throaty voice and glittering black eyes, is the current rage of Mexico City. Getting a table for her 2 a.m. show at the fashionable, mirror-ceilinged Club Capri requires luck and pull plus about 150 pesos ($16.40) per person cover charge, a record price for a Mexico City night spot. At the Iris Theater, where Lola dances before her nightclub show, tickets are priced at 15 pesos, but scalpers get as much as 50.