You can get disks no problem, changing requires a bit of a technique and care. Its not so easy as other cars.

12mm is very close to 11.8mm, its likely they will be past the limit part way through the new pads. Not sure how much you can push it, but if the disks are not flat I would have renewed them, I like good performing brakes.

The disks are probably not warped, they just do not wear evenly across the radius. Pad quality and regular changes affect this too. If they warp they will vibrate during braking, but that is rare in solid disks.

The pads and disks will wear to each other, but its unlikley they will flatten out evenly, its not really a problem just an indicator they need changed. The squeal might calm down once they have worn in. Try to brake gently until you have them worn in. 200miles at least I'd say.

If you are not a fast driver they will probably be fine otherwise you want new disks,pads and fluid. Bad performance usually means brake fade once they get too hot, that can be pretty scary, but you have to be rally driving to make it happen.

Im not a fast driver and definately dont brake heavily! The squeeking has eased and only seems to occur when Im braking at a very slow speed.

Where can I get new discs when the time comes? I live in the Uk....

Almost anywhere, I did a thread on Mtec disks made in N.Ireland. Just search the forum or google, really not hard to get atall.

Thanks, I've just had a look at Mtec's website and all their discs seem to be dimpled or grooved and not smooth like mine, does that matter?