However not a single one that I have come across allows you to add modules, without prior approval by the network admin.

You aren't going to be able to add modules without approval from the admins unless you do one of two things. One, get root or some type of admin access or two, compile them into your home directory and use the modules from there. You can check here for how to do the second option.

In general, approval shouldn't be a problem so I would just look for somewhere that has responsive administrators or, if you want to compile modules yourself, gcc.