Can use any 2.5" sata hdd also you need a hdd slim cage... find both on ebay!
Or you can use a bit of card top and bottom to hold the hdd in place. You must secure the drive so it cant move about.
Otherwise the hdd kind of floats held only by the sata port... not recommended as a slightest move of the ps3 can dislodge it!
See my vid about 3 minute mark. Whear i do this on a PS3 slim for an example.
https://m.youtube.com/watch?v=eUpZWiXCoFM