paypal agrees to link these gift cards
you know of other payment processors, where you can do the same
There is a service I just heard about https://www.cardcash.comyou know of other payment processors, where you can do the same
They are new but never tested them out so be wary.
Also worth mentioning they are more targeted towards people who are in the united states, so this might be a problem for you if you aren't.