Melt butter in a large ovenproof skillet over medium-high heat; add onion and celery. Sauté 8 to 10 minutes or until vegetables are tender and liquid evaporates. Remove from heat. Stir in breadcrumbs, cranberries, and next 5 ingredients. Let stand 10 minutes. Spoon breadcrumb mixture into a large zip-top plastic bag; set aside. Wipe skillet clean.
Cut pork loin into 6 (1 1/2-inch-thick) chops. Cut a 1 1/2-inch slit in one side of each chop, cutting to but not through other side (about 1 1/2 to 2 inches), to form a pocket.
Snip one corner of bag, and pipe breadcrumb mixture evenly into slits in pork. Rub both sides of stuffed chops evenly with steak seasoning.
Cook chops in hot oil in ovenproof skillet over medium-high heat 2 to 3 minutes on each side or until chops are browned. Cover skillet with lid or aluminum foil. Bake at 350° for 20 to 25 minutes or until thermometer inserted in pork registers 155°. Remove from oven, and let stand 5 minutes or until thermometer registers 160°.