Charles Dallara, managing director of the Institute of International Finance (IIF) who has been negotiating on banks' behalf, said after a meeting in Frankfurt with some Greek creditors that he was "encouraged" about the prospects for a deal.
A senior Greek debt agency official agreed.
"I would expect ... by the end of November at least we should have a proposal," he said, speaking on condition of anonymity.
Under a now-defunct deal in July, private bondholders planned to swap existing bonds for new, longer-maturing paper worth 21 percent less to help Greece as it stumbled under debt currently equivalent to 162 percent of GDP.
It soon became apparent, however, that the 'haircut' was insufficient and last month the IIF agreed with Greece and EU leaders to take a 50 percent loss to put the country on a more sustainable path back to solvency.
However, the swap is far from a done deal.
Greek officials have been meeting individual bondholders around Europe, and may travel further afield, said the debt agency official.
Reaction from financial institutions to the proposed new deal has so far been "mixed," he added.
"The deal is certainly more aggressive initially (than the previous one) but if we end up having a more sustainable debt I think this will be beneficial for everybody," the official said.
He also said that Greek officials had not yet sat down with the IIF, despite its mantle as official representative of creditor banks.
"The IIF is only one of the counterparties," he said.
In Frankfurt, Dallara said holders of Greek debt had formed a committee of creditors to negotiate a deal and hoped talks would start as soon as possible.
The two sides now have a limited time to thrash out the details in order to unblock financial aid that Athens urgently needs to avoid a hard default, something that would badly shake the euro zone.
Implementation could come as soon as early January, the IIF chief said, though he pointed out that international lenders' approval of Greece's new, bigger bailout was crucial to an agreement.
To get that, Athens must satisfy EU, IMF and ECB inspectors with its efforts to shrink its budget deficit and show it has cross-party support for the bailout, neither of which are certain.
A deal is likely to build on many of the principles agreed in the abandoned July agreement.
"I don't envisage a broad range of options this time," said Dallara, who held talks with new Greek Prime Minister Lucas Papademos, a former ECB vice president, in Athens on Wednesday and said he sensed new momentum from Greece's leadership.
The finance ministry in Athens said fewer than four options would be presented to bondholders and could include a combination of bonds, cash and guarantees.