Toss the onion, bell pepper, cilantro and garlic with 1 tablespoon olive oil in a 6- to 8-quart slow cooker. Rub the pork chops with the cumin, 3/4 teaspoon salt and several grinds of pepper; add to the slow cooker. Drizzle with the remaining 1 teaspoon olive oil, squeeze in the juice of 1 orange and add the squeezed orange halves. Cover and cook on low until the pork is very tender, 7 to 8 hours.
Cook the rice as the label directs, sprinkling the peas on top of the rice during the last 3 minutes of cooking. Remove the pork chops to a bowl; discard the bones and orange halves and shred the meat with 2 forks. Stir the vinegar and the juice of 1/2 orange into the slow cooker. Season with salt and pepper; add the juice from the remaining 1/2 orange to taste.
Return the pork to the slow cooker. Fluff the rice with a fork, stirring in the peas. Serve the pork with the rice; top with cilantro.