What to do if I only want to study master not PHD with a professor

I decided to study math after graduating from business department. I entered a 2-year taught program in the same university in Asia and used the time to take all the necessary courses. In the first year, I have studied elementary real analysis, complex analysis, abstract algebra and topology. This is the first term of my second year, I took differential geometry, Fourier analysis, graduate real analysis and functional analysis. My grade is OK and currently I am applying for a research program. My final goal is to go to a top program in US to study my PHD. Since I know it is very competitive, this year I decided to apply a research master only and apply PHD after I gained two-year research experience.

There is a tenured professor in my university whose research interest is nonlinear PDE focusing on fluid dynamics. I am very interested on his research topic and I have made an appointment with him to explore the possibility to do research under his supervision. However, after chatting with one of his student today, I was told the professor usually only accepting student who is willing to continue studying PHD with him. I understand the reason. Since it's a pure math subject, in the first two year, student can only take the basic course, read the basic materials. It's almost impossible for a student to produce any good results after the master. He is very famous in the area so he has a lot of students to select. He don't want to waste the money and time to train a student for others.

On the other hand, I don't think my university is good enough and it's my dream to work and study with the best students in a top program. Since I will meet the professor in a few days, I want to make some preparation so that I can convince his to support me. I will finish all the necessary graduate courses after this year, which means it may safe me some time so that I can focus on research instead of coursework in the research program. But I still think it's impossible for me to produce the same result as a PHD student in 2 years. But since I am really interested in the area, I still want to have a try and talk with him. Currently I am planning to tell him the truth about my plan. Is there anything I can do to improve the chance of being admitted?

Moreover, there is someone in my department whose research area is related, which I'm also interested (but not that much), say PDE focusing on calculus of variation. Do you think it's OK to study with that area for master and study fluid for PHD? I know the gap is large but I still want to know how much my master research experience and the knowledge will be useful in this case?