That seems about right. No higher than that for a bottom third qb with two years left, including one expensive year.
He played well enough last year to show he is startable. It depends on whether other teams thought he has any upside left and whether he's been hindered by coaching and surrounding cast.
I think most teams would answer no, but if they thought he could step it up just a little I could see trading a fourth or fifth for a bridge guy/top tier backup.