The speaker in my 1966 Reverberocket II blew. It is a 12-inch alnico with the codes 5812170 137. So I guess that it is a 1958 CTS, can that be right? I bought the amp second hand so it might be a replacement. A couple of questions: 1.) Anyone have any suggestions for an appropriate replacement or upgrade? 2.) Is the original (?) CTS worth reconing or is it better suited as landfill?