To be honest, you’ll be limited. I would recommend a Mossberg 500 variant or a Remington 870 variant. Some Mossberg shotguns comes with rails, heat shields, pistol grips, etc. the same goes with Remington. They even have some with box magazines. It was my pleasure to assist you.

there is not much out there and most likely will never be that much if you are looking for the ultimate as far a modification and aftermarket parts the Remington 870 is the way to go here is a good one to start with budsgunshop.com/product_info.php/products_id/95568/remington+870+express+12+28+rem-choke+mod+wood

Tim, there are a few options as pictured here : xdtalk.com/threads/emperor-firearms-mptac12-12ga-pump-18-5-shotgun-light-combo-183-72-free-s-h.409089/ ---------------- youtube.com/watch?v=AVm3Unq4xwQ