Any Deep Defensive Player pickups or strategy?

[Leonard Henry -2 Yds]

My defense is struggling (12 team IDP). 5 of my linebackers have gone down since the beginning of the season
nate webster, chad brown, jason gildon (not even signed!), boss bailey, scott fujita

I need some sleepers quickly.

Johnathan Vilma has already been accounted for as have recent pickups like Patrick Kerney and Junior Seau - I'm thinking of trading for or picking up entire linebacking trios - anyone think this is a good strategy?

I like Pittsburgh and NY Jets LBs the most.