As Ghost mentioned, I wouldn't use anything but OEM for the mains. The other bearings aren't that scary apart from the roller bearings on the gearbox shafts...the inner races usually stay put on the gearbox shafts. They are quite strong though so you may get away without them. The seals aren't too bad, i've just paid over the odds from a local supplier cause i needed them quickly compared to Ducati prices......
Three bond and o-rings will see the rest back together.
Drop me a pm if you need prices