When the cost to restore a radio creeps up past the price of buying two or three newer ones that will run rings around it, I decline.
That's the story with the GE 3-5875 Superbase. Won't agree to fix one of those any more. Same with 23-channel AM only radios, the Realistic TRC-459 and other radios that have passed the 40-year mark. The 86XLR has reached the 45-year mark.
Just because you can, does it mean you should?
Not always. That 40-year mark is where the line between "repair" and "restore" gives way and disappears. If it were a 1977 auto under a tarp in a barn with 500 original miles, you would still need to replace a whole slew of gaskets, seals, belts hoses and such before it could be trusted. A person might wish to just "patch" what's broke in a radio that old, but it won't be reliable without being properly restored.
The issue of parts that haven't been stocked in 30 or more years makes it necessary to have a proper junkyard of parts radios. I explained that I had recently ditched every 85 and 86-type radio from the basement. We hadn't fixed one in decades, and they no longer justified the space they took up, so out they went.
Anyone who wants one of those fixed up should locate a guy with the biggest junkyard of parts-donor radios. We have been actively unloading shelves of pre-1980 radios, and the 86XLRs we had are gone.
Forever.
And they won't be coming back.
73