Hi Jerry,
Happy for you that you found the place and get satisfaction. As told the old woman is very professional, she is the owner of the helmet factory and they can design what ever you want.
This area is very rich of mechanic shops it's not easy to find as it's Thai for Thai but when you take time to drag and discuss, you generally found every thing for bikes and cars in this area of Bangkok, on top as it is the Chinese corner, they have the faculty to import on order quite easily.