Hmm, the 4:3 versions did make it to DVD but finding the old version for things is never easy. It's a common wish however, in Anime circles in particular.
Looking at a predb over scene releases and going back as far as they go I see that the naming standard, as I suspected, didn't hint at neither aspect ratio or resolution.
https://predb.net/search/south.park.s01?page=1
However if you look for DivX or Xvid releases I'd say it's fairly likely they'll be in 4:3 since Xvid by and large had gotten replaced by H.264 / X.264 by 2017 which is the earliest release I can confirm is going to be the remaster since it's from the Bluray that released then:
https://www.dvdsreleasedates.com/movies/4399/South-Park-(TV-Series-1997-).html
The above is likely not fully complete so the remaster might've happened between 2004 and 2017, and this might be readily available information but I'm running out of time...
So basically my tip if you're lazy is look for Xvid/DivX and cross your fingers. If you're not then correlate the remaster date/release date to the predb and look for a scene release from before the remaster dropped.
Yes, it's the next step and an evolution because it is far more of a trust less approach. With VPNs you need to trust your provider. If they "give you up" then you're well and truly fucked. For I2P there is no way for a malicious node operators to parse out who is doing what. And the source code you can vet yourself so no need to trust it. Still if you have actors working together in the nodes, the torrent provider and at the ISP level then you can most certainly find a way to break the layer of secrecy. The barrier is however vast and so far police haven't spent that much effort on piracy because it isn't a serious crime in the eyes of the law. And I don't foresee that they will for many years.
It's also far more accessible than say Usenet and VPN+private trackers. Which is a very good thing for privacy in general.