I don't know of anyone who makes them.. in any case, I would always suggest buying an original antique, and if necessary, have it restored / modified to the mattress size you want. You will have an antique piece and cheaper than having a copy made or trying to find someone who makes them. I have made the exercise and an antique was less expensive than having another one made with good / noble woods.
I have imported several Bilros bed in the past 6 years.
Let me know if you need any help sourcing an antique bed.
Antonio Martins Interior Design