Buying wine in Japan when one is from and returning to somewhere that actually makes decent wine is silly I am afraid. Import costs associated with taxes and transport make any wine here pricier than Germany, London, or Canada. Plus buying wine there offers a far better selection. A $20 wine in Europe can be quite stellar. Here is is likely to be garbage. If you are looking for Japanese wine a better thing to do would be ordering it online for delivery at your hotel in advance of your arrival.