Perhaps you can revive one of these study groups: https://www.reddit.com/subreddits/search?q=spivak
Cross-posting to all of them might reach some people who are interested.
This Baby Rudin group is currently active: https://www.reddit.com/r/babyrudin/
I am getting started reading Calculus by Spivak. (It is a rigorous textbook on Calculus that flirts with Real Analysis) I plan on moving fast, especially on the first few chapters which I read a few months back before refocusing on something else. Are there LWers who want to join in on the fun? If you are in the bay area, we could get together occasionally to do problems and help each other out.