There might be some in the northern part of europa as I seen lots of american vans up there but I don't have any specific links or data for it.
Did't see a sportsmobile in europa yet
In Switzerland we have lots of Ford ambulances with diesel engines.
I am also looking over the US van for long time, visited Sportsmobile Indiana in 1995 and ordered one but had to cancel it unfortunatelly.
Now it is time to get one in, should happen mid 2009.
Regarding importing one to europa, the problem might be with the pollution regulations if it is a diesel with gasoline engines less problems.
One month back I talked about US diesel engines with a french dealer importing US cars, he told me that it can be hard but not impossible to register actually. But with the futur european pollution rules no idea yet...
Check with your local autorities, they are the best to help out.