1/200th of that would be enough to tool and produce your first run, if you incorporate OEM trucks and couplers. I take as much up-front money as everyone thinks. The harder task is selling the product and recouping your investment.
Well, my suggestion was an attempt at humor.
But it was also a suggestion about founding a company, with its own tools and production capability for cars and locomotives, with a marketing department, designers, etc., not putting out a single car, shopped out to another manufacturer.
Many years ago, I did look into having a car tooled, but feedback I got from other modelers about the idea did not lead me to think I could sell enough units to make the project viable.
One of these days, I hope I meet you and you let me buy you lunch and you can tell me how on earth you figured out that a BAR Magor car would be a successful product.