well now, as for the trem you'd havwe to buy a whole new trem unit but fear not, just unscrew it from the body and you'l see the end of the collet is cut into four, just squeeze with pilers and it'll hold the trem arm in nice and tight.
for pickups most people here will recomend seymour duncan antiquities.
I can't say much for getting individual saddles but a mustang bridge isn't a hard thing to find and it'll work although the low E will still come out with force.
Don't know whats up with the high e though, my high e is fine and has only broken once through trem use it never goes out of tune, maybe a tuning head problem, tighten the screw holding the head on.
