I know that there was a larger version of this in pixiv, but I guess it was deleted already...
I've checked all of the related tags (フラワーナイトガール, 花騎士, ラベンダー(花騎士), スズラン(花騎士), スズラン and ラベンダー) and didn't find any matches. So yeah, unfortunately it looks like it was deleted. The only source I got was with google-fu's help and it leads here
