Welcome! As @Sk1Bum pointed out, both the amp and tuner can be serviced, but you may also wish to keep in mind that used TX-11s are quite inexpensive in working condition. So a quicker and potentially less expensive solution might be to pick up a replacement TX-11 from CL, FBM, or eBay. Yes, these wouldn't perform as well as a properly restored & serviced model, but depending upon how much FM you listen to, it might be a workable solution for you.