[dirtyroboto]

As said, you can find many Gacha machines dispensing really good charms and other stuff. There are 2 hotspots in Akihabara I know of that will gladly take your money in exchange for J-Rail stuff.

There are also many hobby and model shops that are way beyond what you are used to in your own country. I know quite a few top class ones that cater for train otaku. You should be advised to avoid these places less you desire to end up poor and pay excess baggage.

If you need to find this stuff when you come here then PM me and I will try to sort out a day or two to help guide you.