On ancient Korean women:

The history of pre-Joseon Korean women in general is a very underexposed subject in English, and going further back to the Three Kingdoms period (let alone specifically Silla) stretches even Korean language scholarship pretty thin. Also keep in mind that all of it essentially relies heavily on interpretations of the Samguk Sagi/Yusa (and archaeology), so they probably are worth reading at some point.

To start with, Women of Korea: A History from Ancient Times to 1945 (ed. Yung-Chung Kim) is the only English language book I'm aware of that has a substantial part focused wholly on pre-Joseon women. Sadly it's fairly dated now, being written in the late 1970s, but it's basically the only place to get a broad overview on the subject, covering belief, social status, dress and arts, and so on.

For specifically Silla women, to my knowledge (incidentally the status/history of ancient Korean women is one of my biggest historical interests, so if I'm missing anything, feel free to point it out; I would always love to learn more) there is one English language scholar (and actually one of the pioneers on gender archaeology) -- Sarah M Nelson -- that has specifically gone into depth. Her book (sadly her final work of history) Gyeongju - The Capital of Golden Silla is probably the closest thing you'll find for what you're looking for; it has a particular focus on Silla's capital, but goes into all aspects of its society, including (relatively) substantial talk about women's history/archaeology since it was one of Nelson's main areas of study. The chapter Rulership in Silla might be of particular interest, and has a pretty important section on how manipulation of the classical histories by (heavily patriarchal) later Confucian historians likely seems to have erased a Silla queen from history.

Specifically on Silla, she also has the chapter "Gender Hierarchy and the queens of Silla" in the 1993 work Sex and Gender Hierarchies (although a lot of it is also covered in her book on Gyeongju). Nelson's other works have a broader focus, but since we know relatively little about specifically Silla women (especially pre-Unification), taking a broader look and making assumptions on how it applies to Silla is kind of essential. Her chapter "Gender and Archaeology in Coastal East Asia" in 2013's A Companion to Gender Prehistory has an overview in a few regions but a section specifically focusing on Korea (and the broader perspective the chapter offers is kind of important anyway--Silla culture wasn't operating in isolation); her book Shamanism and the Origin of States: Spirit, Power, and Gender in East Asia has a substantial chapter on ancient Korea, and women's importance in Korean shamanistic belief systems was a central part of life at the time.

Moving beyond Sarah Nelson's works, Lee Bae-yong's Women in Korean History omits the cultural history of pre-Joseon women, but has a series of revealing biographies of notable figures from the period. Hai-soon Lee's chapter "Representation of Females in 12th Century Korean Historiography" in Women and Confucian Cultures (referring to the Samguk Sagi, our historical source on ancient Korean women, which was written in the 12th century, to those that might be confused) is a really helpful critical look at how the Samguk Sagi and Goryeo society presented earlier women, showing how the Confucian-written history warped how they were depicted. Finally, Yi Seong-mi's "Women in Korean History and Art" also has some discussion of pre-Goryeo women, including status and inheritance.

And sadly, that's about it for history! There are isolated passages in other works, but mostly just going over information that these works more thoroughly cover. Moving onto archaeology there's a little more; Kim Jongil's "Women and Femininity in Prehistoric Korea" from 2011 is an overview of the (scant) data up to the bronze age (so pre-Silla, but still likely relevant to Silla culture). Rachel J. Lee's 2019 article "Gendered Spaces and Prehistoric Households" covering the late Neolithic, which would likely have been similar to common people's lives during much of pre-unification Silla.