No jewelry repair or redesign is too complex for these pros, who’ve accessorized everyone from Billy Crystal to Sylvester Stallone. They’ll replicate a lost earring, shorten bracelets, and restring pearls. The painstaking process often includes sketches, wax models, and castings, all before the trinket is polished to a like-new glow. On a recent visit, staff estimated $300 to rehab a necklace.