Bearings should be 'standard' ie available from any bearing dealer net or walkin worth the name.
Removal is a matter of appropriate slow steady force applied from the opposite side of the bearing
Depends on your access but the hub has to be hollow. Even with locktite on the bearing it should
extrude out with some gentle persuasion. Bearing will have some cryptic numbers on the seal, take the
intact bearing to bearing store or cross ref with google. Doubt they will cost more than $2-4 each. 3/8" all thread, a couple of nuts and washers will allow you to press in the new bearings. Campy hubs highly likely to be Campy splined.