I haven't found anything like SICP (thus my question), but I feel compelled to mention two great practical repos I discovered yesterday thanks to HN, both of which are teaching me a lot about practical type systems:
1. https://github.com/tomprimozic/type-systems (great practical intro to Hindley-Milner and variations)
2. https://github.com/typeclassy/plzoo (collection of mini languages implemented in OCaml, many of which feature different type systems)
Edit: Can't reply to jcurbo yet, but I'd be really interested in that Haskell link if you can remember it.