I have even cut back on a quilt and put a new binding on No one would notice it missing 1/2" all the way around. If not I agree with Iceblossom, make a patch. I have done that too. You will need to be the final judge on how you want to work out this problem. Consider the age of the quilt. I have a stack of quilts ready for mending. A couple are beyond repair. Others quilts need a fair amount of work and others need a great deal of work but have the best potential. Hopefully your quilt is not to worn and a simple fix in all it will take.