Bus from Ikekuburo to Kesennuma

Hi, I checked online that I could get a bus ticket from Ikekuburo, Tokyo to Kesennuma. However, I could not find further details on how to purchase the bus tickets online or whether they have a English website to do so. Can anyone advice me on how to get the bus tickets before I arrive at Tokyo? Thank you.

There is no English website to my knowledge. Here is the Japanese one:
http://www.iwatekenkotsu.co.jp/kesenraina.html

Reservations can be made by phone during office hours (0193-25-2525 or 0570-048985), but I am not sure whether they provide service in any language other than Japanese.

Or they can be made on the internet via one of three websites in Japanese:
https://secure.j-bus.co.jp/hon/RouteList.mvc/Detail?gpcd=030002&rocd=0001&mode=1
http://www.jtb.co.jp/bus/list/clist.asp?CpcdA=0301
http://bus.nta.co.jp/route/list?mode=3&uncd=0301&gpcd=030002&rocd=0001...

Or through convenience stores inside Japan.