As others said, unpickling won't work without sklearn installed; this is how Python pickle works. At the low level when you pickle something you're not saving actual source code for all objects/classes used - pickle just saves class/module names of objects. So you need the same environment to unpickle the data.
https://github.com/nok/sklearn-porter allows to export a limited subset of scikit-learn models to other languages. It does so by exporting parameters of sklearn estimators, and then providing an implementation of 'predict' function in a target language. Implementation of prediction routine is much simpler than training for most models, so it is feasible. You can do the same manually if you absolutely need it, and sklearn-porter doesn't support your models.
But usually it is easier to just ensure environments are compatible, i.e. sklearn is installed and versions of packages match.