Quidditch.
I don't know. If we could somehow fundraise without getting caught, that would be ideal. But setting up a fake charity for this purpose, no matter how clever would be sniffed out easily. It would also be duping people, but I strangely don't have much of a problem getting purists to give us money to then give back to the people they've basically called subhuman.
I'm not sure how anyone else feels, but for those who want to or are able, we could start a pot for any and all sponsorship money. Get it to our teammates or people who can better help the wandless.