I would start by calling Cary Audio. I think you will find they know their products very well and will be more than happy to work with you. You might also try reaching out to Dennis Had directly. He is no longer associated with Cary Audio but started the company, was the designer of your amp and I believe will be more that willing to render an opinion on best way forward.
Amp recommendations
Looking for some advice. My 25 year old amp has given up the ghost and I haven’t kept up with what’s good out there. Instead of sinking money in my existing amp, I’m thinking of replacing it. The amp that went bad is a Cary Audio CAD 300B (none of the tubes are working, one of the rectifiers flashes when turned on, I checked the tube fuses). The preamp is a Cary Audio SLP-70 (I recently had it checked out and retubed it). The speakers are Chapman T-7. I also have a Creek CD-60 and Project 1.2 turntable. Music Meter inter connects. My budget is around $4000 for a new amp. Is this a reasonable budget? What amp recommendations do you have? I’d prefer to stay with vacuum tube but if there are solid state amps that you’d recommend, please do so. I can provide specs on the components if needed. Thanks for your advice.