Hi Jules,
Thank you for using the Support Forum. I am not sure which finisher you have with your machine so I am going to refer you to the specifications for the Light Production C Finisher and the Advanced or Professional Finisher. I hope this information will help you to find the available paper sizes and orientations. If this information does not help please consider contacting your support centre for further assistance.
Am I to understand that to staple from the inserter I can only do 8.5x11 or 11x17 SEF?
Thanks!