P.S. I'm also planning to fork the blockstack client legacy code and add those two commands to import a wallet and extract the private keys for anyone else trying to get their coins out of
Unfortunately this is going to take a wee bit longer than I planned because I have to port escobol's code to Python 3. If I run it on Python 2, the registrar Python module introduces dependency hell which prevents it from being installed from a setup.py.