I have no idea what it would be worth.
I would try asking on taurusarmed.net, they might be able to give you a better idea of what it is worth.
Have you considered just keeping it and shooting it? Load it up with .38 special for the wife, the recoil from .38 special will be easily manageable by your wife. The nice thing about a .357 magnum is that you can load .38 special in it if you want a lighter recoil.