I think we need to give Burke a crack at it before rushing out into the trade market. Had the injury happened pre-draft we could likely get someone. Trey could improve with less dribbling and a better shot selection... He could play a little more like Exum on offense, but provide a better late shot clock option than Exum.
We need to wait... If we are still having issues at the point teams will fall out of contention and potentially look to rebuild or retool. Lowry, Hill, Collison, Bledsoe or Knight, Bradley or IT, could all become available depending on team performance. I'd keep an eye on Houston with Beverly and Minnesota with Rubio (although I really don't understand why Minny people think he's like a superstar). Jennings also might prove he's healthy and be had for a decent price because of the mammoth deal they gave to Jackson. Right now those guys would cost a lot of assets... in January though maybe not. Patience for now.
I'm not a big Burke believer, but I wouldn't give up on him just yet given our current situation at point..