S2 fronts are tricky to do... they have the bearing retained with a circlip that you cant get a hold of the end to remove (haynes manual doesnt show that one!)
My secret trick is to remove the entire hub and press out the wheel flange (the bit the wheel bolts to) after undoing the retaining nut on the rear. Then locate the end of said circlip... mount the (flangeless) hub in a drill press, and drill a very small (like 2 or 3mm) hole into the back of the circlip groove so you can insert a slim pin punch to lift the circlip off the bottom of it's groove and get it out... when you disassemble this description will make more sense...after reassembly the hole can be filled with a dob of silastic to stop water / dirt ingress
Front bearing from SKF is a BA2B 633295 A, but they also list a complete kit, which comes with the dustshield plate, the two V groove rings, the nut a new circlip and of course the bearing... most of the time the V groove seals are worn and need replacing.
Rear bearing for the four speed (and five speed is similar method) is very easy, the bearing is retained by a screw in lockring... take the time to knock yourself up a tool (i.e. cut out an octagonal plate from some thick sheetmetal, find the centre and weld on an old 1/2 drive socket) and the job will be easy...
4 speed and five speed use a different sized lockring... completely from memory the 4 speed is 2" across the flats and the five speed is 2.5inch... I'd need to go out to my shed and look at my bearing tools to confirm...it's just gone midnight so that's not happening tonite :-0
Keep the old inner and outer bearing races... cut a slot down thru the side of them with a metal cutting disc and they make great tools to press the bearings back into the hub and also for pressing the flange back thru the bearing... the slot is so the "tool" doesn't get jammed...
I'm pretty sure I have some OE 4 speed (same as 127/128 too) lockrings, maybe bearings for the rear (SKF 633313C) possibly loose brgs for front of ser2, but no front full kits for ser2...
SteveC