Where you would run into red tape is the importing of the units. DOT standards...blah, blah, blah!
Possibly not though. I imported my Boler
from Canada, and because it was over 25 years old and non-motorized, there was little interest/rules about standards (beyond basic roadworthyness, I suppose, although there were no specific checks for that, either, in my case).
I did have to fill out paperwork (several forms), and had to have the trailer officially "imported," but it was not at all difficult or demanding.
Since the Willerby was built in the '50s, it's over 25 years old.
Of course there may be additional steps with importation via ship, and also I may have had it easier due to NAFTA; I'm just saying that there *may* not be major red-tape issues. It's at least worth checking into if someone is really interested.