Sony's standard practice is to begin discontinuing parts availability around seven years from original product introduction. The SCD-1/777ES has reached this horizon. The last I checked in the US the sled motor assembly was unavailable, but other wear items such as the CD spindle motor/bearing housing and laser were still in stock. The main circuit board was unavailable, but this is rarely a problem area.
Some threads in AA point to non-Sony sources for a standalone motor that can be retrofitted to the sled motor bracket. Best to acquire spares now if you plan to hold the unit, and if you're handy, to perform periodic cleaning & lubrication of the transport. This includes most importantly a spray of deoxit inside the sled motor, and also a dab of grease on the spindle bearing, and a light lube of the sled rails & round & straight gears. If you can't do this yourself I suspect Richard Kern could perform the maintenance.
Some threads in AA point to non-Sony sources for a standalone motor that can be retrofitted to the sled motor bracket. Best to acquire spares now if you plan to hold the unit, and if you're handy, to perform periodic cleaning & lubrication of the transport. This includes most importantly a spray of deoxit inside the sled motor, and also a dab of grease on the spindle bearing, and a light lube of the sled rails & round & straight gears. If you can't do this yourself I suspect Richard Kern could perform the maintenance.