Clara, In the new Knit.1 magazine is an advertisement for sterling silver charms from a company called Charland Designs (charlanddesigns.com). They have pretty nice charms - and I can't find anywhere else online to buy them from. I am hoping that this is a line you might consider adding to the boutique.
Some of the charms include stitch markers, needles, yarn hanks, needle sizer. They are sterling silver.
Nowhere near where I live or may travel sells their stuff either...