You can use the query string to specify the key length
Key length: 384
Private:
-----BEGIN PRIVATE KEY-----
MIIBDAIBADANBgkqhkiG9w0BAQEFAASB9zCB9AIBAAIxAK8aWVD+AMLyu/kb1ecd
ydi/2fAv6y+h/xGd9Z0/nMuC990hE4+odCS6+zYkL4M4GQIDAQABAjAfkqeyM+qd
PDlqpHtATh28KHO6nFlS4GmZ/9jPs6zjauvFzapaZgqtlQ5Azc1gmdUCGQDlogSl
vW5YQG2PE/AnrzI6BFsb57xlPS8CGQDDNXDbgistT9v7p55pSV5C2NuM/NHHXTcC
GQCr70mnh1SNg4AEtxsDu6vRwN0u4a4v50UCGQCdTND2cTvttW5kqTtDSDXG1AyG
3asFZZ0CGQDiBby+kmaJg+ovHt+rgKSJFzaTZSfDH9M=
-----END PRIVATE KEY-----
Public:
-----BEGIN PUBLIC KEY-----
MEwwDQYJKoZIhvcNAQEBBQADOwAwOAIxAK8aWVD+AMLyu/kb1ecdydi/2fAv6y+h
/xGd9Z0/nMuC990hE4+odCS6+zYkL4M4GQIDAQAB
-----END PUBLIC KEY-----