As far as your methodology goes, you might find this of interest.

Otherwise, you're options are limited unless you're willing to give up on the one-piece Cinelli bar. I don't know that they make it with a shorter extension, but even if they do, it'll be pricey.

So short of lengthening you're neighbor, some kind of compromise will need to be made. She can enjoy high fashion in discomfort. Or she can trade style for good fit and comfort. This is a dilemma a woman can appreciate, practical shoes or Jimmy Choos.