*You might also need the proper tool for removing the old, dried-on crystal cement
*Crystal cement- be sure to get the right kind. Not all acrylic cements work with sapphire or glass, and not all glass cements work well on plastic.
*Applicator for the cement- the cement may or may not have its own applicator.
Be careful not to use too little cement or the crystal won't stay in place.
Be careful not to use too much or the dial will be ruined....then you'll have to get a replacement dial! At the very least, the job will look like hell.
If you for the case number, on mechanical watches its the second group of four numbers. You can look up the part number here. The page will take you to the 7n43, but there look like there could be three different crystals depending on the case.