There is a development branch of WP Super Cache that is implementing a plugin for WP-API v2. The pull request on the main github repo can be found here and the dev branch on the forked repo can be found here.
On top of that, jp-rest-cache has been updated to support WP-API v2, but it does still have the composer dependency. If the WP Super Cache plugin turns out not to be stable I will most likely fork the jp-rest-cache code to create a version not requiring composer.