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This is the most complicated 茶箱 of Gengensai's four. According to chanoyu.world, it has close links to 香道: Autumn is both the best time of the year to see the moon (air is clear and stars are bright), and to smell incense (air is wet and cool, and there are no flowers). In fact, it's the only 点前 for tea that involves incense.
chanoyu.world says that all the 道具 should be very humble and 詫び(わび), reflecting the 詫び autumn; so the 茶箱 should not be lacquered, the 鉄瓶(てつびん)should be old an rusty; 茶巾筒(ちゃきんつつ)bamboo. 織部(おりべ)or simple gourd 振り出し(ふりだし). 楽茶碗 or something simple, 茶杓 may be from a material different than bamboo.
In Chanoyu Vocabulary, unrelated to this 点前, they describe the 利休がた 茶箱, which is made from unfinished paulownia wood. Maybe this is suitable?
Personally, I wonder if lacquer wouldn't be great because it would reflect the moon. If it's autumn related, my idea of using a Kūsama-inspired 仕覆(しふく)might be fitting. I like the idea of using a glass 茶椀. The 古帛紗(こぶくさ)could be dark on the outside, and reflective on the inside, so this could reflect the moon light in the dramatic moment when tea is served. The 金平糖( コンペイトウ), I think, could me made to taste like star-light. I think to use a ぞげ 棗(なつめ)and 茶杓 could be very cool. Hare is probably also a fitting motif. For 小羽, I would like to use a black raven one, and I think the うぐいす should be magnetic.
As a 振り出し, one made out of a small pumpkin would be very cute (check Ursula).
This is the most complicated of the 茶箱点前. It is closest to 花, with the addition of a 香合 and the 小火箸(こひばし), as well as the きずえ, 小羽(こばね)and うぐいす.