Silver pendant with British hallmark appraised

While going through some vintage items I acquired from my family for
next project, I found a silver locket pendant with flowers on the
front. On the back there is an anchor hallmark which I found to
repesent Birmingham and the letters JW which I found out to be the
initials of a Joseph Willmore. I would rather sell this item and put
the money into my own business, but don’t know who to go to.