In that budget range ....you have quite a few choices ....look at the Beretta offerings 391's and 3901's / and the Winchester SX3's or Browning Silver series. Browning owns Winchester now ...so they're basically the same gun.
All of those guns are gas operated ...and good solid options.
There are some less expensive semi-autos on the market .....Mossberg, Stoeger, Franchi, etc ....and all of them have pretty mixed reviews...some good/some terrible....
Picking a shotgun is all about "Fit" - so the gun hits where you look / because the rear sight is your eye. There are a lot of subtle issues on shotguns / like is there any adjustabilty built into the gun --- like changeable shims between the receiver and the stock, adjustable combs, etc .../ but stay with something in a 28" or 30" barrel and in a 12ga / and you'll find a lot of guns chambered in 3" ( so you can shoot 2 3/4" or 3" shells). I'm presuming you were talking about "Remington Gun Club" shells - they're a cheaper alternative to the more expensive Remington STS shells ...and they're decent shells. You might also look around for RIO /or maybe Estate shells ...sometimes gunclubs in your area might sell flats of 10 boxes for a good deal.
Ideally before you buy --- you should shoot a number of different guns /and try and figure out what "Fits" you ....length of pull, drop at comb, drop at heel, etc ...are pretty big deals. Most stocks can be modified / with stick on comb pads, etc to adjust the fit ....and some guns come with shims and some don't ...
Have fun with your search ...