It can be done. Thats how we have any of them over here!
Though there may be many ways, I am only aware of three ways that worked. I have done one of them twice, am attempting the second and won't try the third. Here they are:
1. The Non-US Citizen route
If you are bringing it over here as a tourist, then you can simply ship it over here with the proper paperwork, get it insured and drive it around in the states. At this point, you can sell it to a US citizen. The US citizen will need to jump through some hoops to get it properly registered here in the states, but it can be done. Thats how I got my RD07 and RD07a; they were brought over by German tourists and I eventually bought them. Getting them registered is a task that Donna Leek here in California has done a few times now. You can contact here here: pro [dot] reg [dot] service [at] gmail [dot] com
2. The US Citizen route
With the proper paperwork, you can import an Africa Twin into the United States. I am aware of one other guy who did this successfully. I am in the midst of doing this myself. Here's how it works...you have the bike shipped to the states with all of its papers and bill of sale. You will also need an official document from Honda that verify's its age. You will need the bike to be more than 21 years old to get around EPA paperwork. Otherwise, the EPA will not let it out of customs. The best way to do all of this is with a Customs Special Agent. You can hire them in any town that has an international port. So, in conclusion, this route is only proven with bikes that are 21 years or older. An RD07 or an RD07a won't work.
3. In Parts
I have read of a few people who have dismantled their bikes and shipped them over in separate pieces. They then reassemble the bike and get it registered in the states. I know the least about this approach. Perhaps others can chime in if they have had success with it.