Take a look at this
http://www.scottmeredith.com/pages/backlist.html
apart from a few nods to political hard-hitters, they choose to put
science fiction guys most prominently in their backlist.
Yet I primarily know Scott Meredith as a brand due to the striking
fact that practically ALL the stories that used to be included in the
spectacularly popular Alfred Hithcock anthologiess were listed as
being agented by him.
All of those writers (Jack Ritchie for one) seem to be spectacularly
unknown to the world at large.
I googled for info on one of the more talented short story writers
represented therein, (Hal Dresner) and all I came up with was a site
that did a good job of remembering him (along with Silverberg!) for
writing vintage sleaze. :)