You can try creating an account with an offline wallet and getting both the public and private key. Then when importing the private key you supply the account name. I was going to test that this evening.
You may be able to use the wallet_export command on a new wallet with just your newly created account too. Few options to play with on dummy wallets. I haven't tried any of these but the theory is worth a try.
wallet_import_private_key <wif_key> [account_name] [create_new_account] [rescan] Loads the private key into the specified account. Returns which account it was actually imported to.
Loads the private key into the specified account. Returns which account it was actually imported to.
wif_key (wif_private_key, required): A private key in bitcoin Wallet Import Format (WIF)
account_name (account_name, optional, defaults to null): the name of the account the key should be imported into, if null then the key must belong to an active account
create_new_account (bool, optional, defaults to false): If true, the wallet will attempt to create a new account for the name provided rather than import the key into an existing account
rescan (bool, optional, defaults to false): If true, the wallet will rescan the blockchain looking for transactions that involve this private key
aliases: import_key, importprivkey