The reference on changing drives is of course Sound Devices. They have an article on this on their site (if you have not already, do register to the forum, it is the place for this kind of questions. ).
http://www.sounddevices.com/notes/recorders/drive-replacement/From the drives specs it should be
- 5400 rpm (faster only uses more power)
- ata (may be called ata-100).
Given this, none of the choices you had fits this. There are a few on that website that fits the description but I am not really competent to answer which is better.
It might be a problem with your disc. I generally transfer all recordings out of my 722 and does a reformat whenever it is time for a new recording. Sort of believe it has saved me from problems.
By, the way, while you are at it, do check on firmware version as well. Latest version seems stable and has been working for me.
Gunnar