On 04 19, 2012, at 08:21:01, firstname.lastname@example.org
> And then, in a recent episode, we learn that a character has been
> writing SF stories in his spare time and getting them published in the
> SF magazines of the day...
Under nom de plumes, of course, one of which was Ben Hargrove. Not ringing any bells, not that it should. The one rag mentioned was Galaxy, which was a big 'un, for sure. From the general description of the stories he was writing, possibly a Cordwainer Smith type.
I don't know if anyone here ever mentioned the most excellent episode of Star Trek: Deep Space Nine, 'Far Beyond the Stars', which was specifically about a black science fiction writer trying to get a black protagonist in print in this period. Perhaps non-coincidental, the name was Benny Russell.
Chip was asked about this episode, but said at the time he had not seen it- http://www.sfsite.com/06b/srd106.htm
. This was over a decade ago, so I hope he has since then.