Greetings Bruno!
I don't know whether the small dolly wheel that Airstream offered with its Vintage trailers would actually accomplish what you desire. My understanding is that the dolly wheel is meant for shifting the trailer the small amount left or right necessary to get the coupler to align with the ball mount. I do know that some of these dolly wheels will not fit on the electric jacks due to the size of the jack post - - mine fits the Minuet's manual jack just fine, but the socket is too small for the base on the electric jack on my '64 Overlander (26').
I have neighbors with a smaller, lighter trailer and they use a device similar to the one at the URL below when manuevering their trailer into its driveway parking area:
Trailer Mover
At one time, these were available with greater capacities than the one listed but they may have been discontinued.
Good luck with your search!
Kevin