Japanese link building

We require 20 links built over 2-3 weeks from Japanese sites only, using a mix of Japanese & English as anchor text. Speed is not the focus here, quality of links is! Links will need to meet quality guidelines established with the supplier we choose, but spam blogs and the like will not be accepted. We need to build links with real value for our sites, and therefore we want to work with link builders who know and adhere to SEO best practice for link building. This is just a tester project as we will require more links on an ongoing basis that are the same high quality. We will also need links from other countries in the future, so we're looking for long term suppliers. Preference will be given to Japanese suppliers