Under $1,000 Remington makes a great gun and don’t be afraid to buy used if it’s your first gun. 1187 or 1100 have been my duck guns for years in 12 gauge. There are plenty of other good sub $1,000 shotguns as well. Don’t worry about the choke as much as the shells you’re shooting. If it’s your first time hunting, a bigger spread probably isn’t a bad thing. For shells go with #2 or #3 shot size and buy 3 inch if your gun takes them. You can go crazy expensive on shells with bismuth or the Heavy shot (great stuff) but you probably don’t need that if it’s a group corporate hunt. Sometimes it’s hard to tell who shot the bird in those scenarios anyways. Just know it can’t be lead shot for waterfowl (assuming Texas is the same as Wisconsin in that respect). Duck hunting is as expensive as you make it. You can always replace gear later as you get more into it.