Having lived in Japan, although a while ago, I can say I have never felt like such a stud. I never had any desire to look for a pro because there were a lot of pretty amateurs wanting to play. I will say that Japanese women seem to be more submissive, so you have to take charge, and be like, "lets go back to my place now" and they often won't say otherwise. Remember, YOU are the novelty over there, and you won't see them again, so be bold and go for it. Please be aware that I am NOT saying to force them, merely be the dominant one.
Man, I'd love to go back. If you are just looking to pay and play, then go elsewhere as stated, Japan is not the place to look.