The official Hobonichi store (1101) does offer shipping to the US, though it is a little on the expensive side due to the overseas shipping required. The benefit from ordering there is that you have access to all of the official covers and accessories you may want, whereas US retailers tend to carry a limited selection in stock. As far as I know, there aren't any US companies that sell the Japanese Techo, since they have an English translated version available. Kinokuniya does have some imported goods though, so it could be worth checking out?? Someone who has visited one could be of more help there.
As for mechanical pencils, both Bagels and I at the very least have used some in ours and find that the paper still works quite well for it! The only downside being that because the paper is very thin, coarser leads might drag a little and wrinkle the paper if you write with enough force, but you'd have to have a super heavy hand to do it. Azizah of Gourmet Pens mentions the paper being
too thin and smooth for harder leads though, so it really depends. They just so happen to be popular with fountain pen enthusiasts because of the unique way the paper handles inks.
