I am not aware that Palomino made a hard side PUP, the one I've most often seen is the Apache.
Today there are A-Frame pop-ups that have hard sides folding into place, but no extensions beyond the box (e.g. A-Liner and clones from Rockwood/Flagstaff and Jayco/Starcraft).
TrailManor built a foldable travel trailer in which both ends collapsed over the box, no fold up sides, ends overlapped the box and each other; there has been an effort to get back into production, but I've seen no trailers at any dealer in my area.
HiLo built a trailer in which the upper part elevated above the box, no folding except for a tip-out couch space on some models. This brand also failed, but there is a current attempt of revival.
Tom Test
Itasca Spirit 29B