Imported cars have traditionally been very expensive in Japan, but for some reason it is cheaper to have it imported for you than to buy it from a normal dealer. If you do it that way, however, the steering wheel of German and American cars is usually on the wrong side for Japan. Strangely, most older Jags and some other British imports do too.
The book Learning to Bow suggests that having a steering wheel on the other side is actually a further selling point as it emphasizes how exotic having an imported car is, but I’m not convinced that showing how much effort you went to to save a few pennies is something you necessarily want everyone to notice. Instead, I’ve always assumed that it is easier and cheaper to get old MGs and Jags from America, where they were briefly very trendy but soon went out of fashion. There’s also probably not enough demand for British cars to set up imports directly from the UK.