For people who don't like following links, here's the Dillman & Will advert mentioned by
fhammon.
California Digital Newspaper Collection
The company gets this write-up in the 1886-7 CD.
LAPL
And here's the advertisement from page 142.
LAPL
I haven't found any photographs of the store, and Dillman & Will only seem to be listed in the 1886-7 CD.