I looked into this recently.
There seem to have been several different designs of disc used on the 1150 over the years. The discs on the 1200 are the same as one of these designs, but I'm not sure which!
If you can find some 1150 discs and inspect them before purchase, it should be reasonably obvious if they are a match for the 1200. I couldn't find any 2nd hand ones so ended up buying EBC items new, just under 100 quid each

Mind you that's cheaper than the BMW part
As far as the bolts, ABS ring etc go, I am not sure, I bought those from BMW. The ABS ring was about 30 pounds and the bolts, washers and collar jobbies came to about £45!
All in all quite an expensive job, total about 800 pounds for the second set of wheels with all fitments. Worth it though for the peace of mind when laning, especially when out with the lads from Stockport
