If you want to buy washi, a traditional Japanese paper, you should visit this place. They are very well stocked and even have computer washi paper.
Daily: 9 am - 6 pm
More information http://www.insidekyoto.com/kamiji-kakimoto-kyoto
Phone +81 75 211 3481
Address Kyoto, Japan
Coordinates 35°0'49.709" N 135°46'2.615" E