Pre-heat the pressure cooker using the BROWN OR SAUTE setting. Season the pork chops with salt and freshly ground black pepper. Add the oil and brown the pork chops on both sides. Remove the browned chops and set aside.
Add the onion to the cooker and saute until the onion starts to brown and soften - about 8 minutes. Add the chicken stock and stir, scraping up any brown bits on the bottom of cooker. Add the carrots, water chestnuts, orange slices and 1/2 cup of orange juice into the cooker. Stir to combine, pushing the sliced down into the liquid. Return the browned pork chops to the cooker, placing them on top of the vegetables and liquid. Turn the cooker off.
In a small bowl whisk together orange marmalade, soy sauce, honey, and two tablespoons of orange juice. Spoon half of this mixture onto the pork chops and reserve the other half to add to the sauce at the end. Lock the lid in place.
Pressure Cook on High for 4 minutes.
Let the pressure drop Naturally and carefully remove the lid. Transfer the pork chops and vegetables to a platter and cover loosely with foil. Reserve half a cup of the braising liquid from the pressure cooker and discard the rest. Return the pressure cooker to the BROWN OR SAUTE setting. Add reserved braising liquid, sugar snap peas and reserved orange marmalade mixture. Bring the sauce to a boil and simmer until it thickens - about 3 minutes. Serve the pork chops and vegetables over rice, pouring the sauce evenly over the top.