They do appear to have been 'sleeved' - but as has been pointed out the surface is so poor that they won't seal irrespective of whether you choose stock lip seals or 'O' ring seals. Even if you were to get them to suitable finish (think of a surface ground finish) they would then likely be oversize. Probably best biting the bullet and buying a set of re-manufactured calipers (with 'o' ring seals).