Yes, they are obtainable in the configuration
you'e described. I just rec'd the exact same
gun ..... black Super Nova Tactical w/CmfrtTk
and 18.5" slug barrel, the tag on box shows
as follows: FPO S Nova Tact R S Slug 18.5"
CIL P/O CMFR/2V TT Mag-Stop.
Haven't shot it yet, but hopefully later today.
Good luck.