Down at the Atlantic City car show/auction this weekend there was a guy painting full size vintage race posters;
oil on canvas. He would do the standard Watkins Glen, Monaco, LeMans, etc but said he would do anything you wanted, within reason. These were full poster size and he charged 150.00 each. The work was really nice.
I am sure you could have him do up a nice poster to include your car for the same price.
He is located in PA and I can dig up his number if anyone is interested.
Roscoe