The items at the July 2 auction include a 1958 cocktail dress for Dior and a 1970s Rive Gauche camel cable-knit sweater trimmed in fox fur similar to one Jacqueline Kennedy Onassis wore.
"What's exciting about the collection is that you see the progression of his career. He was a real style-setter," said Christie's couture specialist Laura Leyfer.
The cable-knit sweater - with a pre-sale estimate of $250 to $400 - is a version of one Onassis was often photographed wearing, a style she owned in several colors, according to Christie's auction catalog.
All of the items are in excellent condition and are relatively inexpensive because they aren't new designs and have been worn, Leyfer said Friday. "That's part of the appeal and it's what makes it a collectible," she said.
Another item for sale is a dusty pink layered tulle evening dress with metallic pink and silver embroidery, which Saint Laurent designed for Dior in 1958. It's could fetch $1,000 to $1,500.
The costume jewelry includes a floral gold-tone metal and crystal stone necklace from 1990, estimated to sell for $1,000 to $1,500, and a hammered gilt-metal "ethnic" necklace from the 1970s that could bring $600 to $800.
Image: YSL Cable-knit sweater