https://mirrors.kernel.org/linuxmint/stable/19.3/
Go to the official Linux Mint website → → Scroll down to "Older versions" or directly visit the mirror archive. linux mint 32 bit download iso
While you can still find the Linux Mint 19.3 32-bit ISO on various archive mirrors, it is because it does not receive security patches, leaving your system vulnerable. The Best Choice: Linux Mint Debian Edition (LMDE) https://mirrors