Firstly, if I want to be historically accurate, Oiwa would have come from a rich family (during the Edo period, which Yotsuya Kaidan is set in, the samurai were of high class, so considering that her husband was a samurai we can assume she was in a wealthy family). There's also the fact that her father, Samon, wanted her to separate from her husband Iemon too (divorces cost money, and the fact that Oiwa's family doesn't need to rely on Iemon's wealth also suggests that they are of wealth).
With that in mind, the typical dress wear for a woman in the samurai class would wear a kosode, a short sleeved kimono.
However Edo fashion was influenced by the design and style that courtesans and entertainers wear. Outside the samurai class, women experimented with a more elaborate kimono - the furisode, which is often seen on the Kabuki stage. Characterised by long, flowing sleeves, the furisode kimono was accented by a large, loosely tied obi.
The third outfit I've decided I wanted to develop is the white burial kimono, which Oiwa is depicted in when she becomes an onryō (vengeful spirit).
Traditionally, and other (ghosts) had no particular appearance. However, with
the rising of popularity of Kabuki during the Edo period, a specific costume was developed.
1. tengan: 天眼 the heavenly eye
2. menpu: 面布 veil
3. juzu: 数珠 rosary; string of beads
4. tekkou: 手甲 covering for the back of the hand and wrist
5. sudabukuro : 頭陀袋 sack; carry-all bag
6. 六文銭 (roku mon sen - 6 images of sen [old coins]) is in the sudabukuro. (The coins are to pay passage into the after-world when crossing the Sanzu River)
7. kyahan: 脚絆 gaiters
8. The sudabukuro is hung from the neck.
9. Obi: 帯
10. tsue: 杖 cane; walking stick; staff
11. tabi: 足袋 Japanese socks with split toe
12. zouri: 草履 Japanese footwear sandals
13. burial kimono: 経帷子 white kimono in which dead person is dressed