Most of the cushioned pin boxes are designed as a replacement for your specific stock pin box. My Demco Glide Ride was and MOR/ryde, Lippert and the others should be the same. My Glide Ride put the pin in exactly the same position as the stock pin box that came off. MOR/ryde should be able to answer your question for you. Just give them a call with the manufacturer and model number of the stock pin box on your trailer. Keystone uses Lippert frames, so you should be able to find the pin box model on the pin box and get and a good replacement. Be sure and get a cushioned pin box designed for the weight of your trailer - it's important so the ride isn't to stiff or too soft.
Rob