There really aren't happy same sex love stories set in this time period as a rule. It's simply true to life unfortunately. For a much more modern but still historical yuri manga set in Japan, consider Moonlight Flowers. It shows a somewhat realistic take on same sex love during the time the work was written, and it really goes to show just how much progress has been made. My heart breaks for the people of the past that couldn't follow their heart in matters of the heart.