I think the right thing to do is hire an attorney to FILE A MOTION WITH THE COURT asking for release of the gun. Call a local firearm attorney and ask them what you should do.
Once granted, you can go to the police agency that stole it from you and they'll have to release it. You'll probably have to fill out a form and give them your SS#. You might consider taking along a locking briefcase to put the gun in to carry it out to your vehicle (even if OC is legal there).
