Oh boy. There's an entire documentary about how autistic the guy who took over the unofficial skyrim patch is.
https://www.youtube.com/watch?v=q6OqJOSmDrYHe was against keeping the older versions of the patch so if I remember correctly there are no official sources for the older versions (he even made some mod sites remove them). You might as well just pirate whatever edition/version you want because you already paid the toll. It would also be a lot easier to mod. Here's a gog version that seems to work with most mods (95%+ from what AI told me) with most incompatible mods having gog specific patches.
https://rutracker.org/forum/viewtopic.php?t=6264072>0.1.3905696 = 1.6.1179, which is equivalent to Steam 1.6.1170But if you really want to play the original one then try following the instruction in this thread (haven't tried it myself though).
https://www.reddit.com/r/skyrimmods/comments/8w487u/unofficial_skyrim_patch_for_standard_version/ 
