Vintage Paris and Nicky

Paris and Nicky Hilton went on a vintage clothes shopping spree last week at Sielian's Vintage Apparel in LA's trendy West Melrose shopping district.

The hotel heiresses racked up $6000 worth of the boutique's sexy form-fitting frocks from the 60s, 70s, and 80s.

Paris alone bought 35 dresses from Sielian's immaculate collection of previously owned one-of-a-kind gowns.

The trendy shop owned by Sielian Lie and Tsutomu Carton has been opened for just one month and is already a hot spot for Hollywood's hippest trendsetters. Everyone from Keira Knightley to the Olsen Twins are coming in to check out the store's latest finds.

We're told Paris, who is known to call stores ahead of time and have them pull outfits for her before she arrives, tried on nearly everything she bought. Nicky played stylist and pointed out ensembles that she knew Paris would think are "hot."

A source tells TMZ that the sisters were very polite and not the divas you would think they'd be.

While on their retail rendezvous, Paris received at least a half dozen calls, while Nicky continuously emailed friends on her blackberry.

Nicky liked one of her purchases so much that she wore the white dress shown here to a Teen Vogue party the next day and Paris swore she would be back for more after returning from her trip to Germany.

God knows 35 dresses is barely enough to get a celebutante through the week!