I'm a huge fan of Kenrich Williams and would like for him to be on the Celtics. I think he makes sense in the back-up 4/small-ball back-up 5 spot that Grant played last year.
My guess is that it would a 1st Rounder to get him. Celtics have some 2nds to throw in as well.
He fits into the Grant TPE, so it helps with the Thunder roster crunch.