Never done a bearing on mine so I couldn't tell you if they are marked up but any decent bearing will be and yes the pickup ring is internal. The other possibility (As I'm sure they are the same dimensions as the other focus models) is they might have fitted non abs bearings.

Yes circlip possition does help lol. Once you've sorted thi and tried sensors that are known to be good and it still doesn't work then the bearings are your next thing to try. Would be worth talking to the place who got them anyway though and finding out exactly what they bought.