They are nice little watches.
Re the crystal the I have no idea but they are cheap enough to buy one and use it for parts. (Or at least they were when I bought mine a few years ago)
I think the movement in these might be a bit better than you think.
I thought it was a ETA base movement.
Just don't get it wet! They had minimal water resistance when new so they have even less now
http://home.earthlink.net/~brendo81/46374.html
A good link for reference
Cheers
John