There is no good pastrami between the Mississippi and the Missouri. You have to make it yourself. Buy three or four pounds of corned beef, cover it in a mix of allspice and cracked black pepper. Smoke it for three or four hours in a water smoker and serve sliced on a fresh loaf of Panera's rye bread. That's about as close as you'll come.
6710 Clayton Rd, Saint Louis, MO 63117