The $18,500 Ralph Lauren purse. (
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A fashion-forward thief filched a handbag that fetches up to $24,900 at an exclusive Upper East Side store, authorities said today.

The woman walked into the Ralph Lauren Store on Madison Avenue, near East 72nd Street, around 3:35 p.m., Feb. 12 and grabbed a pricey brown crocodile bag and waltzed out without paying, police said today.

The purse matched her outfit — a tan three-quarter-length coat, maroon scarf, black pants and black boots, police said.

Police believe the suspect is in her 40s or 50s, with brown hair and a thin build, weighing from 110 to 115 pounds.