It is easy to bring it to the US for up to one year.
I knew a German family which brought a VW Westfalia LT 28 Sven Hedin to the USA on a one year permit. They forgot to take it out of the country within 12 months. Nobody checks on them.
They left the LT Westfalia in the US for 10 years and came every summer for windsurfing.
I bought the car from them in 2008 very cheap. They were scared it would be seized and crushed by US Customs. Only they had to drive it to BC and I brought it back across the border. It was a 1981, so cheap and easy to import because it was over 25 years old.
So nobody had any problems. If someone from US customs found out they kept the car in the US for more than a year and then sold the car here, they could be banned from US soil and car impounded and destroyed.
Your car can get a one year permit very easily, just leave before one year is up, but you can come back on another permit the next week.
Impossible to sell for import here until it is 21 years old though.
PS. Let me know if you want to sell your camper once you are here...