Hack your PSC with Project Eris or Autobleem. Install the VCD Player core via RetroArch. Copy your downloaded .bin/.cue to the ROMs/PSX folder.
These are impossible to find on standard ROM aggregators:
This is the "Holy Grail" setup but requires investment.
Why do people look for these?
The Internet Archive (archive.org) is the primary host for preserved VCD titles.
.bin, .cue, .dat, or .mpg.