PS3 HDD surgery: What are these screws made of?

Generally speaking, any standard height 2.5 inch SATA laptop hard drive up to 500 GBs should work.

If this is a common issue, I suspect that Sony is used Japanese standard screws, which actually require a different screw bit on which the tips are manufactured at a different angle than an American industrial standard. I ran into this issue on my bike, where stripping is a common issue and a Japanese bit is included in its toolbag which is supposed to be used for the tips. Using an American screwdriver commonly strips these screws if more pressure isn’t applied.