the full title is "Narrow Road to the Far North" and is available at most major bookstores, online, although I found a copy at my local Barnes&Noble.
It wasn't uncommon for monks/travelers to keep road journals back then (most of the stuff I've studied dates back to 300-1700AD). Here are some other titles by Basho:
"Journal of Weather-beaten Skeleton"
"Notes in My Knapsack" ("The Records of a Travel-worn Satchel")
"A Visit to Kashima Shrine"