Both are possible. You can research blades advertised online that are of interest and then see them in person while in Japan. Seeing them in person is superior to online only. For example, you may find that a sword looks good in pictures but appears tired in person. And there are many reputable Japanese dealers who post much of their inventory online with prices. You’ll get that same price if you buy from them in person. English speakers at Japanese sword shops can be hit or miss. Aoi Art, Touken Matsumoto, Ginza Seiyudo, and Japan Sword are just a few in Tokyo that I know have good English speakers.
Value varies, too. Some dealers have higher prices due to higher overhead, just like any other business. There are also really nice swords in the U.S. in your price range. You might attend one of the sword shows in Chicago, Las Vegas, San Francisco, or Orlando to see what’s available and to continue your learning. I’ve learned a ton by going to sword shows, asking questions, and examining swords.