Posted: 20/12/2015 at 10:58
It is a commercial variety from a US company called Sakata, so is probably only availablle to commercial growers. However, in my experience some wholesale suppliers will sell to the home grower but it may take a lot of work in locating one as all of their dealers are in the Americas. Here's a link to their supplier page to get you started:
Good luck in your quest Barry.