If you have the whole mount then a standard 3/8 thread CB antenna fits it, which is available at any truck stop or CB shop. A normal (I believe its a 39 inch) fiberglass stick is fine. It will cost you around $20 – $25.00. If part of your ball mount socket is missing then again it can be replaced with any standard CB ball mount that looks the same as yours. Clean up the threads in your ball mount before screwing in the new antenna.
Inside the overhead compartment above the driver’s seat, there are holes cut in the insulation that exposes the rear mount for that antenna. there are three bolts in a triangular pattern and the antenna wire stud in the center. The wires that connect the antenna to the C.B. radio attach to the center stud.
1) The insulated center wire is for the signal.
2) The bare wire is a Ground plane wire that must ground the base mounting plate to the vehicle frame/structure. This allows the antenna to use the superstructure of the motor home as a ground plane. Most truck stops have these antennas or their replacement whip if the base is good. Also any Radio Shack, E-Bay should have this antenna. Any C.B. shop can assist you in tuning in your C.B. radio for the new antenna.