Stop thinking about adding vintage to your store’s collection and start shopping for a stellar assortment now. Where to begin? This article is a great place to start.  Photography by Kenji Toma Prop styling by Eriko Nagata Circa 1900 French Art Nouveau 18k gold and enamel brooch with 36 ct. hexagonal-cut topaz and 1.3 cts. t.w. rose- and Old European–cut diamonds; $100,000; Macklowe Gallery; 212-644-6400; macklowegallery.com No doubt about it: vintage jewels are hugely in vogue, making it the perfect time to add an estate jewelry capsule to your store’s offerings. Whether you’re dipping a toe in for the first time or looking to grow your current business, these pro tips will set you up for success. Buy “Over the Counter” Successful estate jewelers acquire their inventory from a ­number of sources, including local and online auctions, flea markets, and, at the high