You can always use an older (UNSUPPORTED) 32-bit build.
Try this one (it's a lot faster):
http://dl.dolphin-emu.org/builds/dolphin-master-3.5-351-x86.7z
Try this one (it's a lot faster):
http://dl.dolphin-emu.org/builds/dolphin-master-3.5-351-x86.7z
