Is it permissible to pay the expiation of feeding the needy from the funds of a scholarship provided by the state, or must one wait until employment, knowing that there is a long period before employment and a fear of death before paying the expiation?

It is permissible to pay expiation from any lawful money that a Muslim possesses through legitimate means, such as a government grant. It is not a condition that it be from one's wages. The basic principle regarding expiations is that they can be paid at leisure unless their cause was illicit, in which case they become immediately due. Therefore, expiation should not be delayed if you are able to pay it, especially if its cause was illicit.