There is plenty of free agent pitching available. Four of the top 14 starters in terms of fWAR will be free agents (Cole, Strasburg, Ryu, & Wheeler) plus other several other semi-interesting guys in Bumgarner (3.2), Odorizzi (4.3), Gibson (2.6), Hamels (2.5), and Alex Wood.
IMO, there is zero reason to trade for pitching. The hitting class is very underwhelming after Rendon, Grandal, & JDM if he declines his option. A trade would be more justifiable there, but we don’t have a lot of expendable chips.