Initially, Delves' thought to capture the attention of Hisaishi by simply re-creating his Ni no Kuni score as a hobby. Delves set up a Tumblr (aptly title "SamScoresNiNoKuni") to document his efforts, but once word spread, he received an unexpected outpouring of support for his work.
The video you see above is Delves performing alongside an orchestra enlisted by BBC documentary composer Howard Davidson. The SamScoresNiNoKuni Tumblr features an additional 15 songs drawn from the game, and those of you who particularly enjoy Delves' take on Hisaishi's music can download a free, three-song EP directly from the site.
Despite Delves' impressive work, he has yet to have any contact with Joe Hisaishi.