Interesting, after using vanitygen for a long time, I've never tried the encrypt-option.
C:\Users\Ynysmon\Downloads\vanitygen-0.20-win (1)>oclvanitygen.exe keyconv PsTNSPvWJF8mNm2JVSnwsX9fSFymdvvXZxecSABwpXrnkHVfUQi4qt8ekDTcgCm7qBAf
At least on Linux, keyconv is an executable on it's own. It doesn't work for me though:
ERROR: Unrecognized key format
@astralliam: I recommend to create a new private key, after posting the encrypted version online I wouldn't trust it anymore.