Cockie, who finished second in Sandringham's best and fairest in 2012, was previously on West Coast's rookie list from 2009-2010, playing seven games.
He also played under St Kilda coach Scott Watters at WAFL club Subiaco.
The players are one of nine unlisted players given permission by the AFL to train with clubs in the lead up to the drafting period.
Essendon will trial Tom Fields (Labrador) - son of former Bomber Neville - and Nick Kommer (East Perth).
Delisted Brisbane Lions half-back Cheynee Stiller will train with Melbourne, while Andrew Collins (Carlton) and Ben Speight (North Melbourne) will continue training with the clubs that cut them at the end of the 2012 season.
Delisted free agents can be picked up by any club before 2pm on November 13.
