To answer the OP's question strictly, no, there is no modern tactical shotty with a rifled barrel (that I'm aware of). The reason is because slugs are not the favoured load for tactical situations. If a single projectile was to be used, it might as well be a rifle. The main reason to use a shotgun (and be forced to carry less ammo due to the larger size and greater weight of shotshells as compared to rifle ammo) is due to the spread effect and greater energy transfer from multiple projectiles (buck shot or bigger bird shot). Having the option of using slugs is a plus of shotguns, but not their main thing, at least in tactical situations. Having a rifled barrel will take away one's options for using shot, due to the spin imparted to the pellets, forcing the shot into a donut shape, and leading up the rifling. My best recommendation would be to look at rifled choke tubes. According to tests conducted in various locales, there seems to be no appreciable accuracy difference between a rifled choke tube and a fully rifled barrel. If you fired shot through the choke tube, you would still have the problems listed above, but de-leading a short choke tube is much easier than de-leading a whole barrel. You could also just quickly change the choke tube before using shot.