I promised that I would do at least one newer Windows 32-bit Sigil build, and I've fulfilled my obligation. Tell all your 32-bit friends that Sigil 1.3.0 has a 32-bit binary installer that can be downloaded.
Just don't get too used to this happening.
https://github.com/Sigil-Ebook/Sigil/releases/tag/1.3.0
It's the Window Setup file that doesn't have an 'x64' in the file name, in case there's any confusion.