I'm sorry to have to say this, but you've got it all wrong :)
Bars are 25.4mm or 31.8mm only at the stem clamp, the rest of the bars are 22.2mm. So as long as you get a Wald basket where the clamps are a bit spaced out, you're clamping on to the 22.2mm part. The same for the SRAM S500 levers.
GF wants some new bits on her commuter.
She wants a basket on front, with drop bars. It's a single speed so I was thinking a Wald basket with SRAM 500 levers.
But Wald works only with 25.4mm bars.
Are there equiv basket like Wald for 31.8mm bars?
Or should I look for levers that work with 25.4mm bars?