Thank you PertNordin and freewayxx for being my gallant defenders. The cute little wiggly pink egg, which does, by the way, onomatoppoeiaaah, work very well (you're not American by any chance, are you?) only costs 40 kuai including batteries, so even if it does break down in mid-session, one should be able to keep a supply of back-ups in reserve. Happy to see there are more of us free spirits out there in Kunming!
And it was just as you said! My dear, darling husband headed north on his bicycle this afternoon, and after not a terribly long time came across the characters you had posted. First shop was apparently rather sleazy and mainly geared towards impotent men, but the second shop was run by a kind, motherly, middle-aged woman who was able to provide him with the coveted vibrator. It's the cutest little pink egg that wiggles and vibrates very promisingly, I (we!) are deeply grateful. Thanks again!