Largest possible prints for the following scenario:

Hi all. I have a question I would like to ask to those here that know better than me. I am currently shooting with a Sony Nex7 and a Zörk Shift Panorama Adapter with medium format Pentax Lens (SMD Pentax-A 35mm) to produce high resolution panoramas. I shoot the camera vertically and get (using the 22mm full shift each way) files that are nearly 14,000Px long (and something in the whereabouts of 6,000px tall).

I have been asked to produce some of my images in large sizes for a possible exhibition next year. Now, assuming that the images are well exposed, sharp (tripod, remote, etc) and that the methodology involved in the shooting is all correct (let´s not discuss that here), what , in your experience, would be the largest possible prints (high quality) I could achieve with this files? Also, I am not familiar with uprezzing and the involved software, is that a viable option for achieving larger prints without much loss in quality-detail? I would appreciate any insight , I am really not familiarised with this part of photography..

Thanks in advance for all the kind replies and for your help.

Best,

Erik.