I am obsessed by beautiful blank notebooks, note cards, pens and pencils. Millimeter/Milligram from Seoul, Korea is one of those online boutiques I wish I could order from (they don’t deliver except within Korea). You may want to contact them to see if they have a wholesale distributor in your city. Here in San Francisco, you can find similar items carried by the Kinokuniya store in Japantown and in Maido at the Westfield Mall in downtown San Francisco.
UPDATE: If you are in Korea, visit their store at 683-142 Hannam-dong, Youngsan-gu, Seoul, open from 11:00 am to 10:00 pm.
