Sakura Honey was available from Johnny's about 8 years ago. It has been discontinued. I do not know of any source of seed currently. I purchased the last seed Johnny's had in stock at that time. I still have some of the seed though I don't know if it is viable. I have a few started to see if they will grow.
I pulled up Johnny's website on Archive.org and found Sakura Honey listed in 2013. I'm fairly sure that I purchased the last seed of Sakura Honey in 2014. Note that Johnny's was discounting seed in 2013 which means they probably purchased it in 2012 and it was grown in 2011.
https://web.archive.org/web/20130521...c-813-red.aspx