tl;dr - Title chosen; work beginning · 6:15pm Aug 21st, 2012
The Silver Spoon fic I've been talking about is called Sinceritate Argentum.
If you can guess why I chose this title in the comments, I will try and give your OC a cameo. (Limit 3 winners, 6 OCs total)
The only rule limiting the OC cameos is: They must be a pony race. No Griffins or Rockdogs or whatever.