Waiting for a concert to start at a venue in Uguisudani, just north of Ueno, I filled the time I had to kill by wandering around the district, looking for temples, shrines or other interesting spots. I found three temples that I particularly enjoyed: Senju-in, Eishou-ji and Seson-ji, all distinct from each other but very pleasant.
Seson-ji doesn't have a garden, but does have some other features that were interesting to a temple-spotter like me. There were plenty of statues and carvings dotted around: Buddhist deities or saints in a small wooden shelter, lots of stone grave markers which displayed their age in their various states of weathering and wear, a bronze statue of the Goddess of Mercy, holding a baby in her palm with two other children sitting at her feet.
There was also a koshinto, a stone memorial pagoda dating back to 1674, complete with images of spirits, children and animals. Finally, at another shelter near the gate there's a large stone atop an altar, with elaborate images of six Buddhist saints scratched into the surface.
Seson-ji is a few minutes' walk from the south exit of Uguisudani station, on the JR Yamanote line or JR Keihin-Tohoku line