You're looking for one of two very specific models.
16' Heritage Deluxe (used to be sold
as a Spirit Deluxe with side bunk option)
16' Layout 4 (side bath, front bunks)
is more common that the Casita
and is a better layout in my opinion. The front bunks are roomier and the large front window makes it feel more spacious. It has more galley space with a larger fridge
option. It tends to run a bit lighter than the Casita and has more interior headroom (6'2" vs. 5'10" in the Casita). The rear window opens for better ventilation, and the roof air conditioner is more effective in hot weather than Casita's small window unit mounted near the floor. Only downside is the bath is really small and height limited. If you stay in campgounds and only use it for emergencies, it works well enough.
Casita never sold
many 16'ers and discontinued them a few years ago. Most of the units I've seen with the side bunks for kids are older. Casita only rates their top bunk for 80#, while Scamp rates theirs for 150#. That might be a bit optimistic, but it should be good to at least 120# based on my experience.
Casita put most of their effort and numerous improvements into the more popular 17'ers (shown in your sample photo). They are a fair bit heavier and may require a larger tow vehicle due to high tongue weight
. Most of the extra length went into the rear main bed (54"W vs. 45"W in the 16'ers). Doesn't sound like much, but a 45" bed is pretty snug for a couple.
Our 13' Scamp has the same beds as Layout 4, minus the bath and extra galley space. It worked well for our family of four (with some adjustments to the sleeping arrangements). We cook outside most of the time and stay in campgrounds with facilities.
Best wishes in your search!