The key is to use the Sony drive (auto-inject), not the Mitsubishi.
For the sake of reliability, look for one where the pin which detects the disk hole is green, not white. The white ones tend to have problems recognizing if a disk is locked or not. Even better, if you can look at the serial number on the drive (which follows the same format as the Macs), get one made in mid-1992 or later; the eject mechanisms seem to be more reliable.