No, I haven’t seen them in Hokkaido yet, but according to the August 22, 2012 Ottawa Citizen, Seiyu GK, the Japan arm of Wal-Mart Stores Inc, began selling the chocolate and peanut butter Reese’s this spring under an exclusive one-year distribution agreement with Hershey Co. The article states that the Japanese version of the candy is the same as what is sold in the US, except for a preservative that is not approved for use in Japan. The US Food and Drug Administration allows “TBHQ,” which is shorthand for tertiary butylhydroquinone, but some other countries, including Japan have not approved its use. The Japan candies are made in the US without TBHQ and shipped to Japan.
According to the article, Seiyu’s first-month sales amounted to 1.7 times more than Kit-Kat Mini, which had previously been the most popular product in the store’s chocolate line-up, so Reese’s are probably going to continue to be sold in Japan.
I have to admit, they are a candy I am fond of and would probably buy if I saw them in the store here.