Well, my SCD-1 became steadily less willing to recognize discs even with my repeated use of the on/off and open/close controls, so I took it in to my local authorized Sony repair shop last month. (I was going to play a nice tune for my wife, but it took so long to get the SCD-1 to recognize the disc that she eventually left before I could get it to play. I realized that I couldn't put off a repair any longer.)
They replaced the laser head, a $190 component -- it was expensive because it was complex, with both the CD and SACD readers part of the same unit. They also replaced an oscillator crystal, which was a $20 or $30 component. This latter was because Sony had tagged the original oscillator as prone to failure at this age, so its replacement was a preventative measure. With labor and tax, my bill came to $364.
I just hope the unit keeps working another 5 years.