You have a couple of options that will best work for your application. Either a rectangular or linear style of burner could fit your needs. Both units are a complete drop in type that uses a push button manually operated gas valve. The burners are housed within a pan that uses a mounting lip to allow the burner assembly to hang on the perimeter of the opening. This ensures the burner is recessed by only 1 1/2 inches, which is optimal for the best performance. The linear styles is approximately 5 inches wide by 24 inches long. It is the Hearth Products Controls 24 Inch Stainless Steel Linear Trough Gas Fire Pit Burner Kit with Manual Ignition
. The H style burner is a newer item and has not yet been added to our site. Dimensions of that product is 12 inches by 24 inches. Please keep in mind the trough style will have a 50k BTU output, as opposed to 75k for the H style. The H style will have a 12 inch high flame, where the linear will have a 10 inch flame. The BTU requirements will likely make a difference on the size of the supply line you are running.