Maruzen eBook Library (MeL) holds ebook edition of 源氏物語 (the Tale of Genji) from 新日本古典文学大系19 (岩波書店). Easy Navigating Manual for MeL is below.
My Japanese Studies Librarian colleagues at other institutions are also creating LibGuides on similar topic. You may find them useful!
Or, if you want to limit your search to English materials, switch to Advanced Search screen and select Subject field with the same subject heading and set the Language limit to English.
Other Subject Headings you might want to try:
Replicas of the Tale of Genji scrolls (miniature version) are available in UI Special Collections. If you'd like to know how to handle real Japanese scrolls, check out this online tutorial from the Freer and Sackler Gallery on YouTube: Safe Handling Practices for Japanese Handscrolls