SI.com does have him as the top defensive FA available
http://nfl.si.com/2014/03/07/2014-nf...gent-bargains/
1. LaMarr Houston, DL (Oakland Raiders)
It’s not known why the Raiders, in desperate need of great players all along their roster and with $65 million in cap space, haven’t sewn up one of their few legitimately high-quality homegrown prospects. But Houston said last December that he feels the Raiders are ready to move on without him, a notion that head coach Dennis Allen doesn’t share. At 6-foot-3 and 300 pounds, Houston is amazingly versatile — he can play three-tech tackle, end and even outside linebacker with consistency and effectiveness. Houston bagged a career-high six sacks last season, plus 27 quarterback hurries. And if playing in Oakland has decreased his profile enough that he’s not seen as a near-elite player around the league, someone’s going to get an enormous bargain.