Never found one. The manual that is.
In the CNET Laptop Troubleshooting forum, at the top is some bonus material but I'll take your word you can't find the manual. Why? Because Sony does not consider this an user serviceable item.
But many laptop drives can be replaced with standard notebook DVDRW drives and we choose SATA or IDE and we are done.
HOWEVER there are some that want that factory bezel and for those we buy the drive from Sony.