Raw milk

Is there any place in Japan where you can find raw milk?

What exactly do you mean by "raw milk"?

If you mean milk straight from cow and not pasteurized, then the only chance I can think of is visiting a dairy farm and ask for the milk to drink on the spot.

Following types of milk you can find at shops/supermarkets:

pasteurized milk (at lower temperature for not damage the flavour) LTLT: 低温殺菌牛乳（ていおんさっきんぎゅうにゅう） teion sakkin gyuunyuu
[note: most milk sold in Japan is UHT)

non-homogenized : ノンホモ牛乳（のんほもぎゅうにゅう）
(rather rare, may not available at ordinary supermarkets.)

Raw milk presumably means it's untreated.

As above, short of going to a farm and asking for some straight from the cow, most likely not. There is always the chance that untreated milk is infected with TB or other microbes so I very much doubt anyone here would risk selling it commercially.