Serrated Bone Dirk is affordable and has a useful snare proc for soling.
Unfortunately, it doesn't proc until level 27.
http://wiki.project1999.com/Serrated_Bone_Dirk
Also, Smoldering Brand for offhand will proc for you.
http://wiki.project1999.com/Smoldering_Brand
Though, in groups, you don't want to be proc'ing...