I definitely think we can get something decent for Cole.
But I don't think we will trade him, because as of right now he is part of our four man DT rotation, along with Pickett, Williams, and Jolly.
Harrell isn't ready to play yet, and to trade Cole would mean you send Harrell out for snaps when you know he isn't ready to play. That can be stunting his development, since the last thing you want him to do now is lose his confidence in his abilities.