How much to add on the turret?
A ballistic turret can be ordered for any Swarovski "BT" rifle scope. The models that have the BT are:
59020 & 59024 - Z3 4-12x50 BT Plex or 4W
59760 & 59764 - Z5 3.5-18x44 BT Plex or 4W
59880 & 59884 - Z5 5-25x52 BT Plex or 4W
59410 - Z6 2.5-15x44 BT Plex
59510 - Z6 2.5-15x56 BT Plex
59610 & 59618 - Z6 3-18x50 BT Plex or 4W
59910 & 59918 - Z6 5-30x50 BT Plex or 4W
All of the X5/X5i models come with exposed target turrets so a ballistic turret can be ordered. For the Z8i scopes, the BTF (ballistic turret flex) is a separate option that can be ordered as an elevation and/or windage turret for any of the Z8i models. A ballistic turret would have to be ordered separately as well for the Z8i.
Any authorized Swarovski dealer can order a PBC "personalized ballistic turret" from Swarovski for $189. Outdoorsmans can do turrets for the Swarovski scopes, however I have sent back turrets that were not engraved properly.