What to do with broken McIntosh Pre-Amp

Thank you all for your recommendations.  I’m going to try that $50.00 Chase controller for now and send out the pre-amp for repair later.

The folks at Audio Classics are  THE source to repair your  MAC. Steve or any of his staff will work with you and offer options or solutions based on your conversation They ‘hear’ you and are as honest as the day is long.  good luck whatever route you choose 

Search the Internet for a good used tubed preamp like an Audio Research, Conrad Johnson, or Vacuum Tube Logic

 get a Music Reference RM-5, 3 tube preamp, they last forever

I use an Acurus R11 from EBay. R10 would work too. $300 and it is a highly regarded entry level,  quality piece that works well witn Mac and can be upgraded too. Good military spec components. You would be able to sell it later too. I use mine with a McIntosh  MC250.   Sounds great.