Secure method for encrypting 32 byte private keys
SIV is a mode specially designed for this purpose. SIV-AES would be a good choice, but it has the same issues as AES-wrap; not many implementations. If you use a GCM you should make sure that the IV is unique (if your plaintext is ever not random you would otherwise be in problems).

As for the password based key derivation function: yes, PBKDF2 is good, with a high enough iteration count. For this kind of data though I would really make sure that the pass phrase has enough entropy. You could consider scrypt with a relatively high memory usage and possibly additional key access restrictions / authentication.