The 36-year-old has taken help of an antiques dealer to buy the timepiece, reports contactmusic.com. "He's asked a friend who's a rare watch dealer to email him photos of options. John's a great giver, who finds unique presents," a source said.
Mayer will have to go a long way to beat last year's gift, when he got her a custom designed guitar covered in intricate designs, including her initials and the date they first met.
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