LONDON—A drawing of a bear’s head by Leonardo da Vinci is seen fetching up to $16.7 million, potentially setting a record, when it heads to auction in July, Christie’s said on Saturday. Measuring 7 cm (just under 3 inches) squared, “Head of a Bear” is a silverpoint drawing on a pink-beige paper. The auction house says it is “one of less than eight surviving drawings by Leonardo still in private hands outside of the British Royal Collection and the Devonshire Collections at Chatsworth.” It will lead Christie’s “Exceptional Sale” on July 8 in London with a price estimate of 8 million to 12 million pounds ($11.14 million—$16.71 million). That could beat the 2001 sale for Da Vinci’s “Horse and Rider” for more than 8 million pounds ($11.14 million), a record for a drawing by the Italian Renaissance master, according to Christie’s. “I have every reason to believe we will achieve …