I will go looking it's been awhile. The gentleman specified the parts replacements with easily available substitutes. I believe he quoted the condensors were a particularly poor type originally. The transistors were also under rated or of poor quality.
I also suspect that the ones that come back to life after resolderinmg may have dropped out of service while fairly new. I was never sure it was bad solder joints or the heat was travelling up a components leg and reactivating it.
Although if these units were manufactured by the phillips electronic industry in europe. They never could seem to production solder reliably when others had it down pat. It got to the point I refused to work on their stuff.
Track back to this thread in a few days to see if I have found the information. I too have a few I should do.