replace RV entrance door hinges?

My trailer's entrance door is sagging. The hinges are worn out. I use this trailer to haul cargo daily for work, and I estimate that the door has been opened and closed upwards of 40,000 times.

How hard is it to replace these hinges? Or am I better off buying a new door/frame assembly?



It looks like the hinges might be riveted to the frame, but I'm not sure if those are rivets or something else. They screw to the door, so that part is easy enough to detach.