So my exhaust split right behind the cat. Think it could be welded? Or should I look to replace whole system?

Pics

Take it to a good exhaust shop. Chances are it can probably be welded.

if you do replace it dont go cheap, all the standards subie parts from advanced and nappa autozone ect… well lets just say this, none of those mufflers last more then a year. At 10 years old with the original still intact, i say weld that shit up.

I burned thru 2 mufflers for a forester in 2 years, both broke at the welds because they are on such thin metal and such poorly done work.

depends on how long you want it to last till your replace the entire thing I suppose

Honestly I am betting sean fillner would be a good person to ask that one too, I cant say myself.