This won't help you with the bunk beds, but might be of interest to you and others concerning the king bed. We replaced the foam mattress with 2 twin bed air mattresses. I know what you are thinking, I'm not sleeping on an air mattress, but hear me out.
Here's the link to what we purchased:
https://airdream.net/shop/mattresses...mattress-twin/
These mattresses have springs and quilted top on them. They come with an inflation pump and inflate in about 30 seconds each. They are not cheap at $320 each. They are very, very comfortable and not like any air mattress you have ever slept on.
They are about 6 inches shorter than the original foam mattress and the 2 pushed together are about 4 inches more narrow. They inflate to around 10 inches high, but deflate enough to still allow the back shell close with no problem.
After we we slept on them a few nights and loved them, we took the cover off of the original foam mattress. I then cut a 6 or 7 inch piece from the width of it to fill the gap created by the shorter air mattress. We put the piece at the foot of the bed. We also purchased a folding two step stool to make it easier to get into the 6 inch higher bed, remember, inflated it is 10 inches high.
We love the air adjustability, much like a sleep number bed. We also love how much more comfortable they are than the original foam mattress with the sprins and quilted top. If you are worried about the mattress leaking air, they can be patched or replaced for $185.
I hope this may help some of you as it did us.
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