Good suggestion, but you might want to read this first:
Importing Trailer to US
The new (post-bankruptcy, c. 2009) Bigfoot
company will not issue US DOT certification letters for pre-bankruptcy trailers. So if it's less than 25 years old but built before about 2009 and does not already have a US DOT sticker affixed to the trailer, there will be significant additional hassle and expense to import.
Over 25 years old, like the one in the ad, is straightforward.
This may not even be an issue with fifth wheels. Anybody know when they made the last one? It's been a while, I think.