The barrels from the '870 Tactical' are threaded, but they have a front sight 'base' for a rifle sight. You can simply replace it with an XS big dot or whatever. I picked one up in the EE for about $125.
Barring that - Casey is the man... he can thread any barrel for you.
I wonder if the Carlson's (of choke tube fame) replacement barrels are available in Canada?
They make a 18.5 bead model, thatt's chrome lined as a bonus, for the same or not much more money than Remington wants for the same setup.




























