Solution usually easy and cheap---
Not expensive, but not always easy to source a good solution for a mirror issue, which doesn't look cobbed on, wrong-biked, or Chinese ebay part.
A eureka moment came for me when I noticed that my son's Honda CB500X black mirrors were a dead match for my Forza's black mirrors - but with a longer stem!
Solved the problem with my Burgman mirrors after several months of searching when I found a bike shop in the U.K. selling perfect match, correctly threaded, chrome rods to extend my Burgman's mirror stems by 2".
Both fixes looked absolutely stock.
And can't fault Asian scooter makers for selling scoots or bikes with mirrors too short for Americans. We don't buy enough of their products for them to notice. Fitting ourselves on a scooter is our problem, not theirs. We're lucky they sell any scooters here.
Stig