Don, that is a great gun!! As a matter of fact, I will be getting that very gun in the Muzzleloader version for next year's deer season here in NY. It can shoot rings around any slug gun, all the way out to 200 yds.!! As far as getting a choke tube for the shotgun barreled version I really don't know? You might want to give the factory a call, they should be able to tell you which custom choke tubes out on the market can be used in that gun of yours.<img src=icon_smile_big.gif border=0 align=middle>
"Spring Season....the Best"!!!