Unpleasent or not, I wouldn't harrass an elderly man that has nothing to do with this. Did you contact the postal inspector in the area?
Instead of hiring a lawyer in his hometown, It would be cheaper just to go to his house and beat the knives out of him. Sometimes people get scared if they think they're being followed or someone is out to get them. I know it might not be the best way of dealing with him but it's the way our father's took care of shit like this and to tell you the truth, if someone steals from me, they're getting their ass kicked, even if I get my stuff back or not. Eventually, they will learn their lesson.