I picked up a micro cable at a local - uh, variety? store, aka Fred Meyer, but probably that's specific to the northwest. Wally World? I happened to get a retractable one, brand name ReTrak. Maybe look in the phone / ipad / tablet sections.
And sugismimi - Happy Anniversary!
btw, Nanos are not made to be rebuilt. More along the lines of a carto, use it 'til it gunks up, and toss it. (I did run one through an ultrasonic cleaner for a while, then put it on the heat vent for a couple days to dry, with marginally acceptable results. Haven't heard of anyone else trying to clean them - as in what's the point?)
Having dropped and broken one, I of course had to totally take it apart. It's like a tiny carto tank, bottom coil. Of course, tiny is almost it's name... I do like them for new flavors, as I find them a cheap and easy device.