Yeah decent adult sized cribs are very hard to come by actually.
I know pro nannies usually get their cribs second hand usually from other pro nannies who are selling up and closing down their business. Try Amazon, Etsy, and other sites like those for second hand ones.
Found one here which might be suitable:-
https://www.babyapparels.com/Deluxe_Baby_Crib.html
I don't know of any companies who sell / make decent ones. In fact I like the lockable enclosed ones with a lockable lid to prevent escape etc etc but these seem to be quite rare.
You might be better off making your own custom crib to get exactly how you want it which would also be easier and cheaper than trying to find one that exactly meets your own needs.