The only thing I can think off for you to exchange those is to find someone in this forum willing to buy them off for you. Trusted escrows (not sure if updated) can always be found
on this list if in case you need one. Escrows act as middlemen on trades that involves two parties willing to exchange good to each other but don't mutually trust each other fully. They ensure that a trade goes smoothly and no one will be burned during the process. Usually, escrows are people who are highly trusted in a certain community and
in most cases, won't scam these two parties since they are already paid a fee.