I understand your frustration with Porsche and eBay. It seems you are singled out while others are passed by. I wonder if a different approach might work ie:
For sale: A tribute vehicle professionly built to reflect one of the greatest automobiles ever made by the iconic company Porsche. Never has any company like Porsche dominate the racing circuits yada yada yada....
Praising Porsche with a tribute might be more acceptable that a replica or imitation.
I'm just say'n.